Police arrested a man earlier this week in downtown Palo Alto for allegedly possessing a stolen semi-automatic handgun that was loaded and equipped with a high-capacity magazine.

Officers were on routine patrol at about 3:35 a.m. on Tuesday when they saw a blue 2018 Nissan Altima parked in the red zone next to the 7-Eleven store in the 400 block of Waverley Street. The car's engine was running and a man appeared to be asleep behind the wheel, according to a press release from the Palo Alto Police Department.

"When officers contacted the man, they saw a black handgun in plain view on the front seat within the man's reach," the press release said. "Officers safely detained the man without incident."

The 9mm semi-automatic handgun in the car turned out to be loaded, equipped with a high-capacity magazine. It was reported stolen in Houston, Texas in 2017, police said.

The 21-year-old man was booked into the Santa Clara County Main Jail on suspicion of possession of a stolen firearm and possession of a loaded firearm, which are both felonies, as well as a misdemeanor charge of carrying a concealed weapon.

Anyone with information about the incident is asked to call the department's 24-hour dispatch center at 650-329-2413. Anonymous tips can be emailed to paloalto@tipnow.org or sent by text message or voicemail to 650-383-8984.

Editor's note: Palo Alto Online's policy is to withhold the names of those arrested for most crimes until the district attorney has determined there is sufficient evidence to file charges in the case. Read our guidelines.