(CNN)A new composite sketch of a suspect in the mysterious Phoenix serial killings was released Thursday.
Phoenix police hunt 'serial shooter' after 7 deaths
The suspect is a lanky Hispanic male under 5 feet, 10 inches tall, said Sgt. Jonathan Howard of the Phoenix Police Department.
The sketch is the newest development in the ongoing investigation into the man they have named "the serial street shooter." It's the result of new witness information.
Police said they have connected seven killings and the wounding of two people to an elusive suspect -- or possibly suspects -- who blasts away at his victims at night with a semi-automatic handgun."All of the witnesses have described that the suspect was outside of his car," said Howard. "We have not found any link between any of the victims to each other or the shooter."
The shootings began March 17, when a 16-year-old boy was shot and wounded while walking on the street at 11:30 p.m., police said.
A 21-year-old man was shot and wounded the next night.
Two people were killed in April and two in June. The last shooting happened June 12, when three people were shot and killed in front of a home around 3 a.m.
Authorities have released a sketch of the suspect and said witnesses describe him as a light-skinned Latino or white man in his 20s.
The shootings are concentrated in the low-income neighborhood of Maryvale, with many of the victims shot while standing outside their homes, police said.
The sister of one of the victims, saying she was too scared to give her name or that of her slain relative, characterized the community's fear in an interview with affiliate KNXV.
"It's unbelievable that there is this monster that has done so much harm, that nobody is coming forward," the woman said.
"All of these people were so good. Good people with good families. And now they are gone in the blink of an eye because of a monster."
Whatever the killer is called -- the monster of Maryvale, the serial street shooter -- police said they won't catch a break until someone speaks up.
"We want the public to know that it will take a tip from them to stop this violence," Howard said.
Police said they've received descriptions of the suspect's vehicle ranging from dark sedan to light sedan. They said they are not ruling out the possibility that the shooter changed cars.
CNN law enforcement analyst Art Roderick, a former U.S. marshal, said he believes the killer knows the Latino enclave of Maryvale very well.
"So he drives into these neighborhoods, sees someone standing outside," Roderick said. "The victim's age range -- it's from teenagers to the elderly, male, female. So he's just picking targets of opportunity, random individuals outside their homes at night."
There have been no related shootings since June 12.
"It tells me he could well be watching the news, observing what's going on," said Roderick. "Checking the Phoenix PD website. That's one possible conclusion. The other conclusion could be he's moved on to a different area."
Authorities said there is no link between the Maryvale shooting spree and a series of freeway shootings that rocked Phoenix last year.
"No way they are connected with the freeway shootings," said Bart Graves of the Arizona Department of Public Safety. "And the timeline is not right."
Law enforcement agencies and the Maricopa County District Attorney's Office are jointly offering a $30,000 reward to anyone who provides information that solves the serial killer mystery, and they are reminding the public tipsters can remain anonymous.
"We're not just asking for the public to report any suspicious vehicle or persons," Howard said. "But we want them to report any unfamiliar vehicle or person that comes into their neighborhood."