A wildcat strike by clerical and admin staff at a number of Glasgow hospitals is said to be gaining more support.

Last Thursday some 400 workers walked out in a row about pay and conditions.

But on Monday the organisers of the unofficial strike said the number of staff involved was 500 and that they were refusing to call off the action.

The staff are calling for a pay rise of a �1,000 per annum and have said they are not prepared to wait for a national pay deal.

Workers want better pay and conditions

North Glasgow University Hospital NHS Trust has written to staff appealing to them to return to work.

The health union Unison is also urging members to call off the action.

The strike affects Glasgow Royal Infirmary, the Royal Maternity Hospital, Stobhill and Canniesburn Hospitals, and the Dental Hospital.

Scottish Socialist MSP Tommy Sheridan visited the unofficial picket at the Royal Infirmary on Monday morning.

He said: "These workers are essential. The trust often praises their commitment and for 10 months has promised to regrade them and deliver improved pay.

"Unfortunately this has been empty rhetoric. Over 90% of these striking workers are paid less than �12,000 a year."

Tommy Sheridan visited the picket line on Monday

Mr Sheridan added: "It is a disgrace that essential staff like these are forced to take unofficial strike action in pursuit of their reasonable claim."

Staff are angry that their pay negotiations with the trust were put on hold in advance of a national pay deal that would offer equal pay to all administrative staff in the UK.

Most of those on strike earn around �11,000 annually and are calling for an extra �1,000 per year.

Managers said on Monday afternoon that operations at the seven hospitals hit by the dispute would continue as normal until the end of the week.