The decision by two young Westford women to go "pool hopping" landed one of them in the hospital when she jumped into an empty pool.

Jane Gallagher, the mother of 18-year-old Kelsey Gallagher, says her daughter suffered a spinal injury, a fractured skull and a broken wrist when she jumped into the in-ground pool just after midnight Monday.

A 20-year-old woman was unhurt.

Pool owner Chester Cook tells WBZ-TV he did not know the women. He says the older of the two pounded on his door at about 12:30 a.m. Monday when her friend got hurt.

The pool is under repair and had no water in it.

Police say the women were engaged in a game of "pool hooping," or taking a quick dip in strangers' pools. They face trespassing charges.