VANCOUVER - Prime Minister Stephen Harper delayed a stop on his visit to Vancouver after protesters chained shut the doors at the entrance of the Chinese Cultural Centre where the prime minister was to take part in Chinese Lunar New Year preparations.

Supporters of Vancouver's supervised drug-injection site organized a welcoming committee for Harper to express their displeasure with Ottawa's decision to appeal a court ruling in favour of the facility.

NDP MP Libby Davies told her Twitter followers there was an "impressive gathering" waiting for the prime minister and the building was covered with police tape.

"It was a peaceful protest in support of Insite (I didn't organize). Didn't see chains on doors. Police moved in and out freely," said the posting.

The site said Harper "should be in parl. Insite saves lives - crazy to appeal court decisions."

Vancouver police said that about 150 protesters chained the doors just before 2 p.m. at the centre, where Harper was to take part in a photo-op at a dress rehearsal of Lunar New Year celebrations.

"Safety concerns arose after protesters chained and barred the doors to the centre, leaving the people inside the centre with no means of exit," police said in a statement.

Officers removed the chains and there were no injuries or arrests, police said.

"The protest was allowed to safely continue without further incident."

Harper, who is in town in the lead up to the start of the 2010 Winter Games on Friday, delayed his visit until after the protesters left.

Harper spokesman Dmitri Soudas said the protesters created a security risk for the members of the public and the media inside waiting for the prime minister.

"This was supposed to be a day of celebration but unfortunately those protesters were very violent and it has to created a serious security risk for those inside," Soudas said.

He blamed Davies for encouraging the protesters, although the NDP MP denied being a part of organizing the rally.

And Soudas defended the federal government's decision to appeal a B.C. Appeal Court decision that upheld a lower court decision in Insite's favour.

The B.C. Supreme Court decision found that health care is provincial jurisdiction, and Insite a health care facility. Therefore, the supervised injection site can operate without a federal exemption from drug laws.