By Josh Levs, Ben Brumfield,
and Karl Penhaul,
updated 3:09 PM EDT, Sun July 20, 2014
Gaza City (CNN)
-- The battle between Israel and Hamas militants in Gaza saw its deadliest day Sunday for both sides.
Eighty-seven Palestinians died, at least 60 of them in Israel's assault on the town of Shaja'ia, the Gaza Health Ministry said.
The Israel Defense Forces said 13 soldiers were killed. Israeli Prime Minister Benjamin Netanyahu, at a news conference, expressed the country's "deep pain" at the loss of the soldiers.
In total, 425 Palestinians have been killed, according to the Gaza Health Ministry. It's unknown how many were militants. The United Nations has estimated that 70% were civilians.