In a season which has seen Jose Mourinho lock horns with his reclusive Russian boss, fall out with his £30-million striker and make outlandish criticism of his opponents, it seemed the only thing missing was a shaggy-dog farce.

Yesterday, that was put right by Gullit, his beloved Yorkshire terrier. Within the space of 24 hours a dispute over the dog's quarantine status led to Mourinho's arrest, a Westminster-wide search, and briefings and counter-briefings from Chelsea, council officials and the police over the dog's exact whereabouts.

The affair started on Monday night as Mourinho attended Chelsea's Player of the Year awards, where he got a call from his wife saying Gullit was being taken away.

On returning home Mourinho allegedly became embroiled in an argument with police and animal welfare officers who wanted to put the dog in quarantine, fearing it had been taken abroad, then brought back to Britain, without jabs.

Mourinho refused and in the melee Gullit was believed to have made a dash for freedom.

Officers decided to arrest Mourinho, who was cautioned for obstructing the police.

Mourinho insisted it had all been a "misunderstanding". His spokesman said: "His pet dog was bought in England from a reputable breeder and has had all its necessary inoculations."

A City Of London Corporation spokesman said: "Our main concern is to find and detain the dog pending our inquiries."

There was confusion yesterday over whether Gullit was still at large. Chelsea officials were saying Gullit had been found safe and well. But Westminster city council said they had had no reports of Gullit being found.

• Guardian Service