Israel launches airstrikes after attack

JERUSALEM (CNN) -- An Israeli woman and her daughter were among three Israelis killed in a Palestinian gun attack, which prompted a retaliatory airstrike late Wednesday against a target in the West Bank city of Nablus, the Israeli army said.

"Due to the horrible terrorist attack that took place tonight at Hamra, the Israeli air force bombed a terrorist target in Nablus," an Israeli army statement said.

The statement did not elaborate on the target.

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Palestinian sources said a large explosion rocked a building in Nablus. There were no immediate reports of injuries on the ground.

Hours earlier, senior Israeli officials said three Israelis were killed when at least one gunman went to the gates of the Jewish settlement of Hamra on the West Bank, north of Jericho, and began firing. At least one other Israeli was wounded in the attack.

The shooting attack began around 8 p.m. (1 p.m. EST) and lasted for more than an hour. Witnesses reported seeing more than one gunman.

One gunman was killed by an Israeli army force as he tried to take hostages from a home, officials said. Local news reports said the mother and daughter were killed by the gunman inside the home.

The Israeli army said it is conducting searches to see if any other gunmen are in the region.