The illegal alien accused of murdering 33-year-old Newman, California police officer Ronil Singh the day after Christmas was planning to cross the United States-Mexico border to flee arrest and was a “known” gang member, according to police.

Gustavo Perez Arriaga, an illegal alien living in California, was arrested on Friday after he allegedly shot and killed Singh — a legal immigrant from Fiji — during a routine traffic stop, as Breitbart News reported, on December 26.

Over his police radio, Singh called out “shots fired” and as police arrived at the scene of the traffic stop, they found the officer on the ground with a gunshot wound. Singh was transported to a nearby hospital where he later died.

During a news conference on Friday, Stanislaus County Sheriff Adam Christianson said Perez Arriaga was planning to flee to Mexico and had “known gang affiliations” with the Sureños street gang, noting that the illegal alien had multiple Facebook pages and many aliases.

“We also know he was trying to flee to Mexico. That was his goal was to get across the border,” Christianson said.

“There’s plenty of photographic evidence on and in social media, Facebook, and other platforms that clearly shows him self-promoting himself as a gangster,” Christianson said.

Perez Arriaga also had two previous arrests for drunk driving but was never deported out of California due to the state’s sanctuary state policy, which bans local law enforcement from cooperating with federal immigration officials, thus shielding criminal illegal aliens from deportation.

Perez Arriaga is from Mexico and crossed illegally into the U.S. at the southern border into Arizona at an unknown time within the last couple of years. Police are not aware of any prior deportations of the illegal alien.

“This criminal … crossed our border illegally into Arizona some time ago,” Christianson confirmed.

“He’s been in this country for several years,” he continued.

Christianson said the illegal alien had day laborer jobs in California and that there is “no longterm consistent employer” that law enforcement officials are aware of at this time.

Law enforcement officials said the illegal alien committed the killing of Singh alone but was aided in evading police by two illegal aliens — 25-year-old Adrian Virgen and 27-year-old Erik Razo Quiroz.