Peter den Oudsten, mayor of the Dutch town of Enschede, says a total of 14 people were injured when the roof at the southern end of the FC Twente stadium collapsed around midday Thursday. Three people were treated at the scene.
The cause of the collapse was not immediately known.
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AP's earlier story is below.
ENSCHEDE, Netherlands (AP) — A section of a Dutch soccer stadium collapsed during off-season construction work Thursday, trapping people underneath, police said.
No match was being played at the FC Twente stadium at the time of the collapse and those trapped were believed to be workers. Local newspaper De Twentsche Courant, citing unnamed workers at the stadium, reported on its website that 12 people were injured in the accident.
Police did not immediately give an official number of victims. The local hospital declined comment and referred media to the Enschede Municipality, whose staff did not return calls.
"People are trapped, but we don't know how many," police spokesman Jan Lamberts told The Associated Press.
Part of the roof caved in around midday (1000 GMT). Photos posted on local news websites showed a large section of the roof had crashed onto a bank of red seats behind one of the goals.
Phones at the club went unanswered and the team spokesman did not immediately return a call seeking comment. The team, Dutch national champion in 2010 and runner-up last season, was training in the southern province of Zeeland at the time of the collapse.
Twente is in the third qualifying round of next season's Champions League and is scheduled to host a match at the Grolsch Veste stadium on July 26-27 or Aug. 2-3. The exact date will be decided next week.
The construction work was intended to increase the stadium's capacity to 30,000 from 24,000 by adding a new tier above existing seating.
The stadium is on the edge of Enschede, 160 kilometers (100 miles) east of Amsterdam. Part of the city was destroyed and 22 people were killed on May 13, 2000, when a fireworks storage depot exploded.
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