Israeli forces struck a series of targets throughout the Gaza Strip on Thursday, killing 18 Palestinians, including five boys playing soccer near the town of Jabalya, as a new round of violence threatened to fuel stronger Israeli military action.

Huge crowds of Palestinians continued to stream into Egypt across a breached border from Hamas-ruled Gaza for a second day Thursday. Egyptian border guards took measures to control the flow, but they did not try to halt the crossings.

Tens of thousands of Palestinians streamed into Egypt from the Gaza Strip to buy fuel, food and other supplies Wednesday after masked gunmen used land mines to blast down sections of a seven-mile fence dividing the border town of Rafah.