(Adds details)

JERUSALEM, Jan 6 (Reuters) - Three Israeli soldiers were killed and about 20 were wounded by an Israeli tank shell fired in error during fighting in the Gaza Strip, the military said on Tuesday.

A military spokesman said a tank had fired on a building that the soldiers had occupied in the northern Gaza Strip on Monday.

Four of the wounded were in serious condition.

The incident caused the Israeli military's highest casualty toll since the Jewish state launched its operation in the Gaza Strip more than a week ago. (Writing by Joseph Nasr)

AlertNet news is provided by