Slideshow ( 5 images )

GAZA (Reuters) - Israeli aircraft bombed a tunnel under the border between the Gaza Strip and Egypt on Tuesday, killing three Palestinians inside, medical workers said.

An Israeli military spokeswoman said planes attacked the tunnel after Gaza militants fired rockets into southern Israel on Monday, slightly wounding one soldier.

Palestinian medical workers said three workers in the tunnel, part of a system used mostly to smuggle goods and weapons into the Gaza Strip, were killed and six wounded when the tunnel collapsed in the attack.

Gaza’s smuggling tunnels, which still number in the hundreds despite air attacks and an Egyptian crackdown in which some have been blown up or flooded, are a frequent target of Israeli retaliation for attacks by Gaza’s armed Palestinian groups.

Smugglers send weapons and goods through tunnels to Gaza to circumvent an Israeli-led blockade.

The level of cross-border violence between Israel and the Islamist group Hamas, which controls the Gaza Strip, had been relatively low in recent weeks.

In January, Israel ended a devastating three-week military offensive into the coastal territory aimed at ending Palestinian rocket fire into southern Israel.