Sean Carmeli

Sean Carmeli, left, is seen with Rabbi Asher Hecht in Jerusalem's Old City in this undated photo. (Rabbi Asher Hecht)

A man from Texas was one of at least two Israeli soldiers from the United States to be killed in Gaza this weekend as fighting between Israelis and Palestinians intensified.

Sgt. Sean Carmeli, 21, grew up on South Padre Island in the Gulf of Mexico, just off Texas' southernmost tip, a local rabbi told the Los Angeles Times.

"He had always a cheerful smile. He was always optimistic about life," said Rabbi Asher Hecht of Chabad of the Rio Grande Valley.

Carmeli's Israeli-born parents lived on South Padre Island for more than two decades and built a beach business there, said Hecht, who called himself a close friend of the family.

Carmeli began high school at St. Joseph Academy in nearby Brownsville, according to his Facebook page. Then, wanting their son and two daughters to experience a larger Jewish community, his parents moved the family to Israel about five years ago, Hecht said.

Carmeli -- who used the Hebrew first name Nissim -- was a member of the Israel Defense Forces' Golani Brigade.

Max Steinberg, a 24-year-old who grew up in Woodland Hills and was a member of the same brigade, also was killed in Gaza this weekend.

It was unclear exactly how Carmeli and Steinberg died, but the Israeli military announced Sunday that 13 members of their brigade were killed by militants this weekend in the northern Gaza Strip. Seven of them died when an explosive device hit an armored vehicle, one in a firefight, two in a separate attack and three in a burning building, the Israel Defense Forces said.

At least 100 militants have been killed since Thursday, when Israel began the ground phase of a military offensive that is now in its 13th day, Israeli reports said.

The invasion has been aimed at combating Gaza's network of underground tunnels channeling rockets and militants. Israel regards the tunnels as an acute strategic threat, designed for carrying out cross-border attacks and kidnapping civilians or soldiers. Fourteen such tunnels, dug from Gaza and believed to extend into Israeli territory, have been found so far.

Since Israel's military cautioned civilians to move out of targeted areas, more than 60,000 Gazans have taken shelter in United Nations facilities in recent days, but many others have remained in their homes as the death toll has climbed toward 370.

A total of 18 Israeli soldiers have been reported killed in the campaign. More than 1,700 rockets have been fired at Israel, killing two civilians, since the fighting began July 8.

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