PHOTO: KSWB
Now playing
01:47
FBI says American a top terrorist threat
PHOTO: CNN
Now playing
01:35
See what security looks like outside US Capitol
Now playing
00:00
Bash: This is why key GOP senator is fighting Biden's stimulus
PHOTO: YouTube/Everyday Astronaut
Now playing
01:19
Watch SpaceX Mars prototype rocket nail landing, explode on pad
WASHINGTON, DC - JANUARY 16:  Physician to U.S. President Donald Trump Dr. Ronny Jackson listens during the daily White House press briefing at the James Brady Press Briefing Room of the White House January 16, 2018 in Washington, DC. Dr. Jackson discussed the details of President TrumpÕs physical check-up from last week.  (Photo by Alex Wong/Getty Images)
PHOTO: Alex Wong/Getty Images
WASHINGTON, DC - JANUARY 16: Physician to U.S. President Donald Trump Dr. Ronny Jackson listens during the daily White House press briefing at the James Brady Press Briefing Room of the White House January 16, 2018 in Washington, DC. Dr. Jackson discussed the details of President TrumpÕs physical check-up from last week. (Photo by Alex Wong/Getty Images)
Now playing
03:14
DOD releases scathing review of former White House physician
PHOTO: CNN/Getty
Now playing
02:10
'Highly misleading at best': Dale reacts to Pence's op-ed
PHOTO: Gov. Cuomo's office
Now playing
03:35
Gov. Andrew Cuomo addresses women's allegations
Commanding General District of Columbia National Guard Major General William J. Walker testifies before the Senate Homeland Security and Governmental Affairs/Rules and Administration hearing to examine the January 6, 2021 attack on the US Capitol on Capitol Hill on March 3, 2021 in Washington, DC. (Photo by Greg Nash / POOL / AFP) (Photo by GREG NASH/POOL/AFP via Getty Images)
PHOTO: GREG NASH/POOL/AFP via Getty Images
Commanding General District of Columbia National Guard Major General William J. Walker testifies before the Senate Homeland Security and Governmental Affairs/Rules and Administration hearing to examine the January 6, 2021 attack on the US Capitol on Capitol Hill on March 3, 2021 in Washington, DC. (Photo by Greg Nash / POOL / AFP) (Photo by GREG NASH/POOL/AFP via Getty Images)
Now playing
03:01
DC National Guard commander: 'Unusual' Pentagon restrictions slowed response to Capitol riot
Supporters of President Donald Trump hold up their phones with messages referring to the QAnon conspiracy theory at a campaign rally at Las Vegas Convention Center on February 21, 2020 in Las Vegas, Nevada.
PHOTO: Mario Tama/Getty Images
Supporters of President Donald Trump hold up their phones with messages referring to the QAnon conspiracy theory at a campaign rally at Las Vegas Convention Center on February 21, 2020 in Las Vegas, Nevada.
Now playing
03:00
Hear why QAnon supporters believe Trump will be president on March 4th
FBI Director Christopher Wray testifies before the Senate Judiciary Committee on the January 6th insurrection, in the Hart Senate Office Building on Capitol Hill in Washington, DC on March 2, 2021. (Photo by MANDEL NGAN / POOL / AFP) (Photo by MANDEL NGAN/POOL/AFP via Getty Images)
PHOTO: MANDEL NGAN/POOL/AFP via Getty Images
FBI Director Christopher Wray testifies before the Senate Judiciary Committee on the January 6th insurrection, in the Hart Senate Office Building on Capitol Hill in Washington, DC on March 2, 2021. (Photo by MANDEL NGAN / POOL / AFP) (Photo by MANDEL NGAN/POOL/AFP via Getty Images)
Now playing
02:55
Watch FBI director debunk conspiracy theories pushed by Trump supporters
WASHINGTON, DC - FEBRUARY 10: Neera Tanden, nominee for Director of the Office of Management and Budget (OMB), testifies at her confirmation hearing before the Senate Budget Committee on February 10, 2021 at the U.S. Capitol in Washington, DC. Tanden helped found the Center for American Progress, a policy research and advocacy organization and has held senior advisory positions in Democratic politics since the Clinton administration. (Photo by Anna Moneymaker-Pool/Getty Images)
PHOTO: Anna Moneymaker-Pool/Getty Images
WASHINGTON, DC - FEBRUARY 10: Neera Tanden, nominee for Director of the Office of Management and Budget (OMB), testifies at her confirmation hearing before the Senate Budget Committee on February 10, 2021 at the U.S. Capitol in Washington, DC. Tanden helped found the Center for American Progress, a policy research and advocacy organization and has held senior advisory positions in Democratic politics since the Clinton administration. (Photo by Anna Moneymaker-Pool/Getty Images)
Now playing
01:33
Neera Tanden releases statement on pulling her nomination
PHOTO: KCAL/KCBS
Now playing
01:41
Multiple people killed in crash after SUV and semitruck collide
nigeria kidnapped schoolgirls released Busari pkg intl ldn vpx_00000423.png
nigeria kidnapped schoolgirls released Busari pkg intl ldn vpx_00000423.png
Now playing
02:09
Tears of joy and relief as 279 Nigerian schoolgirls return home
New satellite images taken by Maxar show that North Korea sometime in the past year built a structure that may be intended to obscure entrances to an underground facility where nuclear weapons or nuclear weapons components are stored.
PHOTO: Courtesy Maxar
New satellite images taken by Maxar show that North Korea sometime in the past year built a structure that may be intended to obscure entrances to an underground facility where nuclear weapons or nuclear weapons components are stored.
Now playing
01:47
See images US intelligence claims is a secret weapons site
NEW YORK, NY - JULY 23: New York Gov. Andrew Cuomo speaks during the daily media briefing at the Office of the Governor of the State of New York on July 23, 2020 in New York City. The Governor said the state liquor authority has suspended 27 bar and restaurant alcohol licenses for violations of social distancing rules as public officials try to keep the coronavirus outbreak under control. (Photo by Jeenah Moon/Getty Images)
PHOTO: Jeenah Moon/Getty Images
NEW YORK, NY - JULY 23: New York Gov. Andrew Cuomo speaks during the daily media briefing at the Office of the Governor of the State of New York on July 23, 2020 in New York City. The Governor said the state liquor authority has suspended 27 bar and restaurant alcohol licenses for violations of social distancing rules as public officials try to keep the coronavirus outbreak under control. (Photo by Jeenah Moon/Getty Images)
Now playing
02:29
NYT: Third woman comes forward against Gov. Andrew Cuomo
PHOTO: Courtesy Penguin Random House
Now playing
01:00
These 6 Dr. Seuss books won't be published anymore
John King Magic Wall 0301
PHOTO: CNN
John King Magic Wall 0301
Now playing
03:00
US coronavirus numbers coming down, but not enough
(CNN) —  

The State Department is offering $5 million for information that leads to the arrest of an American citizen on the FBI’s Most Wanted Terrorist List.

An indictment unsealed in federal court on Monday accuses Jehad Serwan Mostafa, 37, of providing material support to al-Shabaab, which the US has designated a terrorist organization for its activities to undermine the Somali government.

“We believe this defendant is the highest-ranking U.S. citizen fighting overseas with a terrorist organization,” US Attorney for the Southern District of California Robert Brewer said in a news release Monday. “Al-Shabaab’s reign of terror threatens U.S. national security, our international allies and innocent civilians. Today we seek the public’s assistance in capturing Mostafa and disrupting Al-Shabaab.”

Mostafa – also known as “Ahmed Gurey,” “Ahmed,” “Anwar,” “Abu Anwar al Muhajir,” and “Abu Abdallah al Muhajir” – was formerly a resident of San Diego, but is currently believed to be in Somalia, according to San Diego special-agent-in-charge Scott Brunner.

He has been linked to the use of improvised explosive devices in attacks in Somalia, according to the release.

Mostafa was raised in San Diego, California, attending high school and college there before traveling to Temen and Somalia in 2005, according to the release. While in Somalia, he fought against Ethiopian forces and later joined al-Shabaab, the release said.

The organization was deemed a terrorist group in 2008, and a year later he was indicted with charges of providing support to a terrorist organization, the release said. The charges unsealed Monday similar charges, but Monday’s indictment expands the scope of the allegations of support.

CNN’s Cheri Mossburg contributed to this report.

Correction: This story and headline have been updated to reflect that the Department of State is offering the reward.