Portland, OR, police arrested a man who watched officers for months from his parked car outside the East Precinct office after finding weapons and ammunition in his SUV, they said Monday.

Officers noticed 39-year-old Eric Eugene Crowl Sunday outside the precinct, Sgt. Pete Simpson said in a news release. Crowl appeared to be monitoring officers, Simpson said.

It wasn't the first time – precinct officers started noticing Crowl in his parked Chevy Tahoe in April, Simpson said. Crowl would film officers and track them during shift changes, he said.

At one point during a traffic stop, officers noted that Crowl had a police scanner in his car and was a "self-proclaimed Constitutionalist," Simpson said.

"Due to heightened concerns about police ambush attacks after the recent incidents in Dallas, Texas, and Baton Rouge, Louisiana, officers contacted Crowl, concerned about his actions," Simpson said. "As officers approached Crowl, ordering him to keep his hands up, he would raise and lower his hands and appeared to be reaching around inside his vehicle."

Crowl eventually got out of the SUV and officers patted him down for weapons but found none, Simpson said.

But when they searched the Tahoe, they found, Simpson said: a 5.56 rifle, a 12-gauge shotgun, two 9 mm handguns, a loaded 100-round 5.56 magazine drum, hundreds of 5.56 and 9mm rounds of ammunition, 5.56 tracer rounds, handheld radios, a police scanner, camouflage clothing and camping gear including sleeping bag, food, camping stove, and lantern, the Oregonian reports.