A US Airways flight was diverted to Philadelphia after a young Jewish man's prayer items triggered a bomb scare, Philadelphia police said.

The incident arose when the man used a phylactery, a small black box Orthodox Jews strap to their head as part of their rituals, police said.

The man was not arrested and the plane landed without incident. The latest incident took place on a 50-seat regional jet originally bound for Louisville, Kentucky from New York's LaGuardia airport. It landed in Philadelphia at about 0900 local time (1400 GMT).