Police arrested a 15-year-old male Thursday inthe case of three college students shot and killed in a schoolyardSaturday night, according to a city official with knowledge of theinvestigation.

The official, who was not authorized to release informationabout the case, spoke on condition of anonymity.

Four friends, ages 18 to 20, were shot while hanging out in aschool yard. Authorities have said robbery appeared to be themotive.

Three of the victims - Terrance Aeriel, 18, Dashon Harvey, 20,and Iofemi Hightower, 20 - were forced to kneel against a wall andwere shot at close range. The fourth, 19-year-old Natasha Aeriel,Terrance Aeriel's sister, survived a wound to her head and ishospitalized.

Mayor Cory A. Booker said investigators were using NatashaAeriel's help to make a break in the case, but he did notelaborate.

Newark has become accustomed to violence, but the killingstouched a nerve. Residents and law enforcement organizations havedonated $150,000 to aid the victims' families and to a reward fund.

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