Health officials and civil defense services in Gaza said that an Israeli airstrike early on Saturday hit a residential building in Gaza City, killing at least five Palestinians. The Israeli army has not yet commented on the attack.

A Gaza ceasefire was reached through U.S. mediation last year, but negotiators have not reached an agreement on the terms for Hamas’s disarmament and the withdrawal of Israeli forces.

Israel says Hamas has again armed itself in violation of its October ceasefire and is carrying out attacks, and that in recent weeks it has intensified its attacks on this group.

Hamas denies any effort to carry out an attack or rebuild its arsenal and accuses Israel of undermining the Gaza peace agreement.