Gaza pounded by Israeli airstrikes

GAZA, July 7 (UPI) -- Explosions were reported early Monday morning after Israel sent airstrikes to assault the Gaza Strip.

The Palestinian News Network reported nine Palestinians were killed and ten injured in the attack that targeted Hamas- and Islamist militant-controlled areas.

After the strikes, Hamas' military wing promised vengeance for the deaths of their members killed in Rafah. On their website, they promised, "the Zionist enemy will pay a heavy price."

Clashes and violence between Israelis and Palestinians are the worst they have been in 10 years. The U.S. has been attempting to broker a peace deal between the two parties but the recent violence makes prospects of progress on the negotiations grim.

Israeli Prime Minister Benjamin Netanyahu promised justice for the murdered teenagers and urged both sides to avoid vigilantism and vengeance attacks.