A helicopter with the U.S.-led Multinational Force and Observers (MFO) in the Egyptian Sinai crashed on Thursday near the resort town of Sharm el-Sheikh, killing seven members of the peacekeeper force, the MFO said.
Those killed were five Americans, a French national and a Czech national, all of them military service members, the MFO said in a statement. It added that one American MFO member survived and was medically evacuated.
An Israeli source briefed on the incident said the crash appeared to have been an accident, with no indication so far that the helicopter had come under attack.
The MFO statement did not give further details of the crash but described Thursday's mission as "routine".
The Israeli military said in a statement it had offered to send a rescue team to the crash site.
The MFO was installed to monitor the demilitarization of the Sinai under the 1979 Egyptian-Israeli peace accord.
In recent years, Washington has been assessing to what extent the United States should participate in the MFO, especially as military coordination between Israel and Egypt has tightened to help beat back an Islamist-led insurgency in the Sinai.
According to its website, the MFO has 1,154 military personnel from the United States and 12 other countries covering an area of more than 10,000 square kilometres (3,860 square miles) in the Sinai. Some 452 of the personnel are American.