Police and Home Office officials have begun an urgent security review after a fathers' rights protester dressed as Batman scaled Buckingham Palace.
The protesters don't only put themselves at risk, said Mr Blunkett
The breach sparked a row in the Commons after Home Secretary David Blunkett defended police actions.
Both Fathers 4 Justice activists involved in Monday's protest have now been released on police bail without charge, pending further inquiries.
Shadow home secretary David Davis said police should get their "act together."
Click here to see how the intruder reached the balcony
Mr Hatch, 32, from Gloucestershire, was removed from a ledge next to the Buckingham Palace balcony after a five-hour protest.
PREVIOUS F4J STUNTS
Sept 2004: Protester David Chick, who is supported by F4J, scaled the London Eye
July 2004: F4J members disrupted a service and held a rooftop protest at York Minster
May 2004: Condoms full of purple flour were thrown at Tony Blair in the Commons
February 2004: Activists climbed bridges and gantries in Bristol, London and Newcastle
January 2004: One protester spent six nights on a gantry over Tamar Bridge, Plymouth
November 2003: 'Spiderman' sat on a 100ft crane near Tower Bridge for six days
May 2003: F4J began to grab headlines when masked men scaled a Plymouth family court
His fellow protester Dave Pyke, 48 - who was dressed as Batman's sidekick Robin - stopped climbing the ladder after armed police threatened him.
On Tuesday three police officers were seen standing at the spot where the ladder was used.
Buckingham Palace said the incident had prevented one group of disabled visitors from getting into the palace because they couldn't park, but that access was now back to normal.
Palace sources played down reports the Queen was furious but said she monitored events closely while on holiday in Balmoral.
Former royal protection officer Steve Park said that as the main centre for royal security staff Buckingham Palace was the "flagship" residence and should be the most secure building.
"This shouldn't have happened," he told BBC News 24.
Opposition MPs criticised the Home Office for failing to prevent the latest in a series of breaches of royal security.
Mr Davis said he would have expected Mr Blunkett to be more "contrite" about the incident.
He told BBC Radio 4's Today programme: "This is a bunch of amateur protesters. What on earth would we be seeing if this had been a serious terrorist attack?"
He said he would consider putting concrete barriers around Buckingham Palace, against the Royal Family's wishes, "if that was the only solution".
In an emergency statement to the Commons, Mr Blunkett conceded that the speed with which the intruders were able to scale the wall was "of concern."
He said police would have shot the protester if he had been judged a terror risk.
On Tuesday Mr Blunkett said there had been similar incidents when Tory leader Michael Howard was home secretary.
He said the government had followed the recommendations of the security service MI5 after the September 11 attacks.
"I'm satisfied we did what was necessary. I'm not satisfied everything worked perfectly last night, although the cameras and alarms did," he told Radio 4's Today.
But he said he did not believe in having security which
hid prominent buildings from the public.
Earlier the Liberal Democrats' Mark Oaten said the situation was "at best highly embarrassing and at worst could have had terrible consequences".
Fathers 4 Justice was set up by fathers who have either no access, or very limited access, to their children and feel they have been treated unfairly by courts.
But one campaigner said stunts do not necessarily help the fathers' rights cause.
President of the Equal Parenting Council Tony Coe said he acknowledged the "real tragedy and frustration" behind such protests.
"That said, we don't think that this kind of unlawful action helps, in fact it alienates the very people that we are trying to persuade," he told BBC Radio Five Live.
He said rather than focusing on the children, the protest had people talking about security issues.
HOW INTRUDER REACHED ROYAL BALCONY
1 Protesters create a diversion at the front gates of the palace.
2 "Batman" and "Robin" climb over low fence at side of palace grounds while security staff are distracted.
3 "Batman" climbs up a ladder on to the roof of an adjoining building. "Robin" comes down after police threaten to shoot him.
4 "Batman" shuffles from roof along ledge to the edge of the royal balcony, where he stages his high-profile protest.
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