The governor of the US state of New Jersey has fired an aide alleged to have orchestrated traffic jams to to spite a political rival.
Governor Chris Christie, seen as a potential Republican White House candidate, apologised for the scandal, which he said "embarrassed and humiliated" him.
On 9 September last year, two of three traffic lanes to the George Washington Bridge, which connects New Jersey to Manhattan, were shut for four days.
The governor and Port Authority officials initially said the decision to close the lanes was part of a traffic study.
But emails and texts made public on Wednesday appear to link the governor's top aide, Bridget Anne Kelly, to the move, the BBC reports.
The gridlock was allegedly engineered to punish a Democratic mayor who did not endorse the governor's re-election.
Mr Christie denied all knowledge of the scandal and said he was misled.
The move caused traffic chaos in the New Jersey borough of Fort Lee, whose Democratic mayor had declined to back Mr Christie in last autumn's gubernatorial election.
Today, traffic flows smoothly over the bridge, but the road ahead is not so clear for Chris Christie.
The BBC reports that he is a paradox - he appeals to one-time Democrats in a way few other Republicans manage - but also relishes confrontation.
It's been a popular mix in the past, but now questions are being asked if his style is appropriate for a president.