JERUSALEM, April 10 (Reuters) - Israeli Defense Minister Ehud Barak said on Sunday that Israel was willing to accept a mutual ceasefire with Hamas militants in Gaza after days of deadly violence.

If they stop firing on our communities, we will stop firing. If they stop firing in general, it will be quiet, it will be good, Barak told Israel Radio.

The death toll since Israel launched its retaliation for an attack on a school bus that critically wounded a teenager on Thursday has climbed to 19 Palestinian militants and civilians.

Gaza militants have fired at least 120 rockets and mortars at southern Israel in that time, the Israeli army said.

Asked if Israel was considering a ground offensive into the Gaza Strip to end Hamas's rule there, Barak said all options were on the table, but that it may not be necessary.

If it will be necessary, we will act, but when it's not necessary, we don't need to, he said. Restraint is also a form of strength.

Israel carried out a devastating military offensive into Gaza in late 2008 with the aim of ending cross-border rocket fire.

(Writing by Ari Rabinovitch; editing by Philippa Fletcher)