The Israeli military struck a series of militant sites in Gaza early Saturday in response to a rocket attack that hit a kindergarten in the Israeli border town of Sderot.

No injuries were reported on either side but damage was caused to buildings. The exchange comes amid an escalation of violence in the West Bank following a pair of fatal attacks against Jewish settlers that has sparked Israel’s largest military surge in two years.

The military said its airstrikes targeted four training sites belonging to Gaza’s Hamas rulers. Late Friday, a rocket from Gaza struck an empty kindergarten, marking a rare successful hit of a civilian target in Israel. Rocket attacks have been sporadic since Israel and Hamas waged a deadly 50-day war in the summer of 2014.

Israeli military spokesman Lt. Col. Peter Lerner said the rocket attack was “a horrific reminder of the intentions of terrorist groups in the Gaza Strip to target communities, people, men, women and children.”