(CNN) The manhunt for a Marine deserter wanted for murder led Roanoke, Virginia, police to shut down all schools in the city on Thursday.

Authorities received a call about 4 a.m. regarding a sighting of Michael Alexander Brown, 22, who is suspected of killing his mother's boyfriend last week in the town of Hardy, about 9 miles east of Roanoke.

The caller told investigators that a man in a black jacket was tapping on a window at Brown's grandmother's house, Roanoke police Chief Tim Jones said. Officers responded and were "able to confirm to the best of our ability that it was Mr. Brown," he said.

While the search continued into the evening, officials said classes will resume Friday.

He switched vehicles, police say

Though Franklin County authorities said earlier this week that Brown was driving a 2008 Lincoln Town Car, Jones said Brown was believed to be driving an RV in Roanoke.

The RV, located nearby, was secured by a tactical team, he said. Brown was believed to be on foot, perhaps looking for another vehicle, Jones said.

Brown was seen at a Franklin County store Saturday, police say.

In addition to asking Roanoke students, faculty and staff not to report to school Thursday, police also wanted anyone who lives within a half mile of Patrick Henry High School on Grandin Road to shelter in place and keep their doors locked. That shelter request was later lifted.

"We continue to urge residents to remain vigilant and report any suspicious activity. Remember to lock your vehicles and your homes," police said in a Thursday evening statement. "The search for Brown continues tonight."

For residents who must travel, Jones asked that they be vigilant, travel in pairs and avoid the area around the high school as Brown may be looking for "other opportunities to go mobile again," Jones said.

Did family bring him to Roanoke?

Brown deserted his post at Camp Lejeune in North Carolina last month, police said.

Around noon Saturday, the Franklin County Sheriff's Office responded to a shooting call in Hardy, where they found Rodney Brown, 54, dead in his home, authorities said.

Rodney Brown's girlfriend -- who is Michael Brown's mother -- called police after finding Rodney's body in the house, said Capt. Phillip Young with the sheriff's office.

Michael Brown is charged with second-degree murder and using a firearm in the commission of a felony. The motive in the killing is unclear.

He is considered dangerous and may be armed with a "shoulder-held, high-capacity weapon," Jones said. He has family ties in the Roanoke area, the chief said, but Brown is believed to be operating on his own, with no accomplices.

The Franklin County Sheriff's Office warned the public Monday that Brown was armed with a high-powered firearm and possibly other weapons.

He is known to frequent national parks and forests, and he may be living in the woods, the sheriff's office said this week.

"We are receiving intelligence that he was in transit yesterday and was seen in several areas outside the Roanoke Valley," Jones said. "I think family is what brought him here. We hope family can appeal to him."

Police: Be on the lookout, but be careful

Anyone who sees him should use caution and call police. Brown is about 6 feet tall and 154 pounds and has brown hair and blue eyes, police said.

Jones described Brown as a "military-trained veteran (who) knows how to navigate avenues of approach and escape, and to maneuver his way around various types of terrain."

"He is navigationally savvy," the chief said. "He's not afraid to change his location. He's not afraid to change his look."

WANTED FOR HOMICIDE: Michael Alexander Brown

The U.S. Marshals are offering a $10,000 reward for information leading directly to the location and arrest of the fugitive -- White, 6 ft, 145 lbs, w/Blue eyes, Brown hair

Call 1-877-926-8332 or 1-877-WANTED-2 pic.twitter.com/lVOXkSeQbW — U.S. Marshals (@USMarshalsHQ) November 14, 2019

The US Marshals Service is offering a $10,000 reward for information leading to Brown's apprehension, Jones said. State authorities, the FBI and the Bureau of Alcohol, Tobacco Firearms and Explosives are also assisting in the search.

Asked whether he had a message for Brown, Jones said, "I'd like him to know that he needs to contact us so that we can make arrangements and he can turn himself in.

"We can do this the easy way. ... He may at this point and time feel like he has run out of alternatives, but he does have alternatives."