updated 3:07 p.m. CT, Wed., Feb. 18, 2009

LONDON - All 18 people aboard the helicopter that ditched near an oil field in North Sea on Wednesday were rescued, British officials said.

The Super Puma helicopter ditched as it approached an installation 120 miles, east of the Scottish city of Aberdeen, said Mark Clark, spokesman for the UK Maritime and Coastguard agency.

The incident occurred about 6:30 p.m. near ETAP Field, which is operated by BP PLC, company spokesman David Nicholas said.

The British military said three helicopters and a plane were involved in a search-and-rescue operation in the area.

Darkness had hampered the earlier rescue operation. The average temperature of the North Sea in winter is 43 degrees, according a department of the Royal Belgian Institute of Natural Sciences that studies the area.

British military spokesman James Lyne told the BBC the helicopter would have been equipped with life jackets, which carry electronic transmitters.