The opening day of sport at London 2012 has sparked a row with North Korea after the South Korean flag was mistakenly displayed prior to their women's football opener against Colombia at Hampden Park in Glasgow.

The North Korean player's names were shown beside a picture of the South Korean flag in an embarrassing blunder which marred the opening day of action at London 2012.

Particularly as South Korea are not even competing in the women's football tournament, though their men kick off their Olympic campaign tomorrow.

Relations between the two countries is tense, and they are technically still at war as no peace treaty has ever been signed following the Korean war from 1950 to 1953.

The team walked off the pitch in anger and only returned to start the match with Colombia an hour later.

An angry North Korean official protests after the wrong Korean flag is displayed at Hampden Park

The North Koreans have received a swift apology, with London 2012 organisers saying: "Today ahead of the women's football match at Hampden Park, the South Korean flag was shown on a big screen video package instead of the North Korean flag.

"Clearly that is a mistake.

"We will apologise to the team and the National Olympic Committee and steps will be taken to ensure this does not happen again."

Hampden Park media manager Andy Mitchell said: "The South Korean flag was shown in the video package on the screen before the kickoff and the North Koreans were naturally very upset about that.

"We have made a full apology to the team and the North Korean NOC (National Olympic Commiittee).

"A genuine mistake was made for which we apologise."

Once back on the pitch, the North Koreans did not seem too affected as they went in at half-time 1-0 up against the South Americans.

Kim Song Hui put them ahead with a fortuitous strike when the ball ricocheted in off her knee as she tried to connect with a cross.

Hui then sealed the win with five minutes to go, taking advantage of an error by Stefany Castaño to chip the ball over the line.

It was a confident and composed start by the North Koreans, whose victory is a signal of their intent at these Games, although many observers consider them fortunate to be allowed to take part.

FIFA have banned them from competing in the 2015 World Cup after five members of their team tested positive for performance-enhancing drugs at last year's tournament in Germany.

But they have allowed them to keep their place in the Olympics.

An attempt by the Australians to overturn the decision was unsuccessful.

-David Gold