GAZA CITY, Gaza Strip - Palestinian policemen angry over the killing of a fellow officer stormed the Gaza-Egypt border crossing Friday, firing shots in the air and forcing European monitors to close the border and flee, Palestinian and European officials said.

The European observers _ responsible for monitoring the crossing and ensuring the terms of an Israeli-Palestinian agreement are upheld _ fled the area, officials said.

The policemen were friends and family of an officer who was killed Thursday in a family feud in Gaza, Palestinian security officials said. They took over the border to prevent members of the two families from leaving Gaza and were demanding the execution of the gunman. They also said no Palestinian officials would be allowed to leave until their demands were met, officials said.

The policemen shut the border's main gate and fired in the air when a car carrying an unidentified Palestinian official tried to enter the compound. The chief Palestinian security officer at the crossing asked the policemen to leave, but they refused.

The border was closed because according to the Israeli-Palestinian agreement the crossing cannot operate if the European contingent is not present, said Julio De La Guardia, spokesman for the European monitors.

"Our monitors are now in the Kerem Shalom military base. When the situation is clear, and these people leave, we will go back to our work," De La Guardia said. Kerem Shalom is an Israeli military base on the Israeli side of the border with Gaza.

The takeover is the latest in a rash of armed kidnappings and takeovers of government buildings that underscores the lawlessness in Gaza and Palestinian leader Mahmoud Abbas' inability to bring order to the coastal area following Israel's withdrawal in September.

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