"It's going to keep my eyes open, that's for sure," Savoy said. "You most definitely don't know what's up someone's sleeve."
Calls to a couple identified as Prescott's parents were not returned Friday, and no one answered the door at their Parkton home.
A former neighbor who said she lived next door to Prescott's boyhood home in Catonsville described him as a shy teen.
"He was always kind of quiet, I didn't really see him outside much," said Betty Conrades. She remembers that he used to get a lot of packages delivered.
Another former Catonsville neighbor, who lived across the street and asked that her name be withheld, said Prescott was an introvert who spent most of his time on the computer.
Both he and his sister were "very good kids," the woman said. "They were a very nice family."
Baltimore Sun reporter Jessica Anderson and the Associated Press contributed to this article.
Timeline of events
Prince George's County police are contacted by a supervisor at Pitney Bowes, who tells officers that Neil Edwin Prescott said in telephone calls, "I am a joker. I'm going to load my guns and blow everybody up." Police say Prescott either had been fired or was in the the process of being fired from his job.
Anne Arundel County officers visit Prescott's Crofton apartment. He responds to their knock on his door by saying he has a gun. They tell him to put the weapon down and come out. They interview him.
Having decided that Prescott might pose a danger, Prince George's County police obtain a judge's signature on requests for a psychiatric evaluation and a search warrant for his apartment.
Friday, about 3 a.m.:
Officers, including a special operations team, return to Prescott's apartment. He comes out and is taken to Anne Arundel Medical Center.
Among the items police found were:
An assault weapon
Nine handguns of various makes and calibers
A high-power rifle scope
A large cache of ammunition and a number of ammunition magazines
Source: Prince George's County Circuit Court Text NEWS to 70701 to get Baltimore Sun local news text alerts