NORTH Yorkshire MPs have called for extra security in the House of Commons after a flour bomb hit the Prime Minister.

Selby MP John Grogan was caught up in the drama yesterday when two men from the campaign group Fathers 4 Justice hurled a purple powder bomb at Tony Blair during Prime Minister's Questions, hitting him in the back.

Last month, the group staged a stunt in York when campaigners donned decontamination suits and hurled buckets of water at the Fishergate branch of Children and Family Court Advisory and Support Service (CAFCASS).

York MP Hugh Bayley said he was sitting behind Mr Blair when the powder bomb exploded. Mr Bayley - who had a private meeting with Mr Blair in the Commons minutes after the incident - said: "If it had been something damaging if inhaled, I was just metres away and there was not a lot I could have done at that stage."

Mr Bayley said he would still provide tickets to his constituents despite the incident.

From the back row of the Labour backbenchers, Mr Grogan saw the missile hurled over the backbenchers towards the government dispatch box.

"It was a bit scary," he said.

"We saw this purple cloud and for a split second it was very alarming."

The campaigners had tickets for seats in front of the Common's glass screen at a charity auction.

Mr Grogan today said the glass screen in the spectators' gallery should be moved so that all members of the public were behind it. "It is common practice for MPs to offer tickets for charity auctions. I think they will have to be more careful," he said.

Mr Bayley said he would still provide tickets to his constituents despite the incident.

Ryedale MP John Greenway agreed with Mr Grogan that the screen had to be moved so all members of the public were behind it.

He said the only people who should be allowed in front of the screen were peers and foreign dignitaries.

Updated: 10:29 Thursday, May 20, 2004