PINE LAKE, Alberta (AP) _ At least seven people were killed and 38 others were injured Friday evening when a tornado touched down at a campground in the western Canadian province of Alberta, officials said.

Witnesses said multiple trailers were flipped upside down at the Green Acres campground and the injured were wandering around in search of friends and relatives. A stream of tow trucks, ambulances, rescue divers and other emergency services descended on the site, about 90 miles north of Calgary.

The numbers of dead and wounded ``are obviously not final yet,'' said Jim Squire, spokesman for Red Deer County.

The storm hit the southwest corner of Pine Lake at the campground, witnesses said, lasted about 20 minutes and brought hail and wind before petering out in the forest nearby.

``There were hundreds of people walking around with scrapes, bruises, people being carried out on stretchers,'' said Andrew Schultz, a weatherman for a Red Deer TV station.

``When you looked in the lake there was a lot of floating debris, like wood, and it looked like parts of trailers,'' said Pat Yates, who was visiting her mother-in-law's cabin on the opposite side of the lake from Green Acres when the tornado hit.

The injured were being taken to Red Deer, about 40 miles to the northwest, and hundreds of others were evacuated to a nearby community hall and an arena.

The weather system that created the tornado could be seen from Calgary, said Blair Morrow of the government agency Environment Canada. A tornado warning had been issued for the area about the same time the funnel cloud touched down, he said.