PHILIP HOLMES/Sun-Gazette

Gunfire erupted at Mulberry and Eldred streets, Williamsport, early Friday morning when an armed bicyclist and an occupant in a passing car, who also had a firearm, fired shots at one another, Williamsport police said. One of the bullets shattered a second-story window at the Curtin Intermediate School at 85 Eldred St., Williamsport, police said. No one was injured, and both gunmen were already gone when officers arrived on the scene about 3 a.m., police said. A handful of casings were recovered, police said.