By Crystal Cranmore and Todd Quinones

PHILADELPHIA (CBS) - A home invasion and robbery that happened in Northeast Philadelphia Monday afternoon is under investigation.

It happened at about 3:30 p.m. on the 3000 block of Vista Street in Mayfair. Authorities say a black man in his thirties knocked on the door of the home, asked for directions and then forced his way inside the home of 81-year-old John and Jane Lesher.

“He was just asking for directions and then he forced his way into the kitchen. He pulled my necklace and he took all of my rings off,” said Jane.

The suspect reportedly threatened the couple and claimed he had a weapon. Authorities say in addition to taking Jane’s rings, he stole rings and a gold watch from her husband, John.

The suspect also stole $300 and two blank checks, according to police.

“He took my whole wallet – all the credit cards, money, cash, everything,” said John, who suffered a bruised hand when the suspect snatched his watch. Mrs. Lesher was not injured.

The couple believes they were targeted because of their routine trip to the bank. Earlier Monday afternoon, John went to his local bank at Frankford and Cottman avenues. He believes the suspect spotted him at the bank, then followed him home. It was only a few minutes after he got home when he and his wife hear the knock at their door.

The couple is now urging people to be careful and not to make the same mistake as them.

“Don’t talk with the door open. Leave the door closed. Talk through the door, anybody you don’t know. You can’t trust them,” said John.

The suspect fled south on Battersby Street, possibly in a white van, and was wearing brown pants and a white shirt.

The investigation continues.