Police in the central California city of Fresno were searching Monday for suspects and trying to determine a motive for the killing of four people at a backyard party and the wounding of six as dozens were watching football on TV. Fresno Police Lt. Bill Dooley said “unknown suspects” sneaked into the backyard at about 6 p.m. Sunday and fired into the crowd. Fresno Deputy Police Chief Michael Reid told the Fresno Bee newspaper and the KSEE/KGPE TV stations that 10 people were shot and that three were found dead in the backyard . . .