PORTLAND – Knives like the one allegedly used in the murder of a store clerk over the weekend are becoming increasingly common, according to law enforcement officials.

According to police, John Mandarelli Jr., 29, of Portland stabbed Jeffrey Rainey in the chest with a knife concealed in Mandarelli’s cane. Police said Mandarelli was trying to steal a pair of windbreaker pants Sunday when he ran out of the store with Rainey in pursuit.

Knives can be hidden in boots, belt buckles and even lipstick applicators, making them difficult to spot.

“We’re getting bulletins weekly, if not daily, about weapons designed not to look like weapons,” said South Portland Police Chief Edward Googins. “Obviously, it’s troubling when people are arming themselves in this way.”

Concealed knives are legal to own in Maine, but state law forbids people from carrying them in public.

“Everyone has a right to protect themselves, and to buy any form of weaponry and bring it home,” said Lt. Ted Ross of the Portland police. “But when you’re on the street and these knives are no longer obvious to law enforcement, it becomes a concealed weapon, and that’s a crime.”

Maine residents can get a concealed weapons permit for a handgun or other firearm, but not for a knife.

Carrying a concealed knife is a Class D misdemeanor in Maine, punishable by up to 364 days in jail.