Old Firm rivalry has been taken to new extremes in the east end of Glasgow by vigilantes, armed with a chainsaw, who cut down two billboards advertising Rangers' new Nike football kit.

The finger of suspicion appears to point at frustrated Celtic supporters, antagonised by the advertisements which were situated on Ross Street and London Road, directly opposite Celtic Park.

The vandals are believed to have struck in the early hours of yesterday morning.

The adverts show Rangers manager Walter Smith next to a blackboard which reads ''nine out of 10 - must do better''. Underneath is written: ''Rangers. Now pushing for top marks in history''.

The campaign plays on the fact that if Rangers win this season's Premier Championship they will beat Celtic's record of nine-in-a-row.

Mr Gerry Madden, General Secretary of Celtic Supporters' Association, yesterday criticised Nike for insensitivity in placing the billboards so close to Celtic Park. He said: ''I don't believe that it's got anything to do with Rangers directly. But whether it is Nike or an advertising agency who decide where the adverts go, it seems totally irresponsible.

''The sensitive situation in Glasgow has to be taken into account in these matters because these adverts are bound to upset supporters.

''But we do not condone vandalism at all, people should be big enough to walk away whatever the provocation.''

Nike denied targeting sensitive areas of Glasgow in order to play on Old Firm antagonism.

A spokesman said: ''I don't think the advert is provocative, I think it celebrates what Rangers have achieved and what they hope to achieve in the future.

''The way it works is we buy packages of sites and can't pick and choose individual sites.''

''We are not out to antagonise or to divide the city, we have several Celtic players who are contracted to Nike, we are merely advertising our association with Rangers.''