Spokesman Paul Colford said the wire service had disabled other Twitter accounts following the attack and was working with the microblogging site to investigate the breach.
"It would be impossible to reconstruct 40 years ago, but I find it hard to imagine this could ever happen again at the AP, " says Paul Colford, the AP's chief spokesman.
"Such increased usage has been compounded by an increase in the HGV weight limit to 44 tonnes and a move to super-single high-pressure tyres, which all adds to the damage caused to the bridge's road surfaces, " Mr Colford said.