Updated

A 27-year-old man and a friend have been arrested in the home invasion robbery of the man's elderly grandmother in Philadelphia.

The robbery happened around 10 a.m. Sunday in the city's Mayfair section. Police say the 94-year-old woman opened the door for a man she thought looked like her grandson. Police say the attacker, apparently the man's friend, punched her, bound her hands and mouth with duct tape and fled with jewelry.

Police later arrested the grandson and his 31-year-old friend and recovered stolen jewelry and the woman's purse. Lt. Michael Gross says there has apparently been tension over money that was loaned to the grandson and not repaid.

Names have not been released. Gross says the men will be charged with robbery, burglary, aggravated assault and other counts.