(CNN) -- The unruly passenger who had to be restrained aboard an American Airlines flight to San Francisco appears to have "mental issues," a law enforcement source said Monday.
Rageit al Murisi was "pounding on the cockpit door" minutes before he was subdued on American Airlines Flight 1561 on Sunday night, said Sgt. Michael Rodriguez.
Murisi was quickly restrained by employees and passengers, according to American Airlines spokesman Tim Smith.
"He never breached the cockpit door. The door was locked," said Smith.
According to San Francisco police, Murisi was traveling with a passport from Yemen. A law enforcement official has said police have seen nothing to indicate links to terrorism, including a possible trial run.
Murisi was placed in flex handcuffs and met by Transportation Security Administration officials and San Francisco police when the flight landed in California, Smith said.
Flight 1561 from Chicago to San Francisco departed at 7:05 p.m. Sunday and landed at 9:12 p.m. The Boeing 737 plane had 156 passengers and six working crew members on board. No one was hurt, Smith said.
It was at least the second incident on Sunday in which a passenger described by authorities as disorderly was restrained.
Continental Flight 546 bound for Chicago from Houston made an unscheduled stop in St. Louis because of an "unruly passenger," a St. Louis airport spokesman said Sunday.
Reynel C. Alcaide, 34, of Burbank, Illinois, got out of his seat and rushed toward the front of the airplane, according to a statement from the Justice Department released Monday.
A flight attendant who confronted him was pinned against a wall, the statement says, and Alcaide repeatedly tried to unlatch and open a flight door on Flight 546. He was charged with crimes involving an aircraft and interference with flight crew members and attendants, both of which carry a maximum penalty of 20 years in prison.
Also on Sunday, a Delta flight was diverted after a flight attendant found a suspicious note in a lavatory, a TSA official told CNN.
The flight from Detroit to San Diego was diverted to Albuquerque, New Mexico, the FBI said, adding that it was informed of "a potential security threat" on the plane.
Flight 1706 landed in Albuquerque shortly before 10 a.m., and agents were on the scene to investigate, the FBI office in Albuquerque said.
TSA spokeswoman Kristin Lee said the flight landed without incident, and all passengers deplaned safely.
"Passengers and carry-ons were cleared by a canine team, and the plane was swept with negative findings," a TSA statement said.
CNN's Shawn Nottingham, Stephanie Gallman and Mike M. Ahlers contributed to this report.