Anti-immigration campaigners protest in Dover
Around 50 people staged a protest at the Port of Dover in support of lorry drivers who face fines if illegal immigrants are found in their vehicles.
The group, which included National Front members, gathered at the roundabout by the Eastern Docks.
Police allowed them to stop the traffic going in and out of the port for about 10 minutes before opening up one lane.
The protesters, holding banners and flags, dispersed at about 14:00 BST after about an hour.
Acting Chf Insp Mark Weller, of Kent Police, said the operation was a success from the force's point of view.
Kent Police said one person was reported for summons for wilful obstruction of a highway.
The demonstration was organised by the group Support the Calais to Dover Truckers.
It had threatened to mount a blockade of the port to highlight the problems faced by drivers crossing from France.
Lorry drivers and their employer can each be fined up to £2,000 per migrant found on their vehicles.
A Port of Dover spokesman said it had remained "open and in full operation" for tourist and freight customers "as normal".
A Home Office spokesman said millions of pounds had been invested in improving physical security and upgrading technology.
Joint intelligence work with the French was designed to "target the organised crime gangs behind people smuggling".
Drivers and hauliers could also avoid the fines if they could show they had taken steps needed "to secure their vehicles", he said.