BERLIN (AFP) - Cologne police said Friday they recorded 22 complaints of sexual assault on the first day of the city's giant carnival, after security was beefed up to prevent a repeat of the New Year's Eve crime spree that shocked Germany.

The number of cases was sharply up from the nine reported on the opening day last year, but police put it down to the greater readiness of victims to report crime.

The complaints ranged from harassment to one reported rape, police said, adding that on average, around 50 sexual offences are recorded annually during the week-long carnival.

Police in the western German city have been struggling to restore public confidence after hundreds of women said they were groped and robbed in a mob of mostly North African and Arab men during New Year festivities.

More than 1,000 complaints have been filed in relation to those incidents.