Eight members of a police force's elite gun crime unit have been suspended for "inappropriate behaviour".

The officers, part of Merseyside Police's Matrix Disruption Unit, are facing a misconduct investigation by their force's professional standards department.

A mobile phone photograph, published in the Liverpool Echo on Wednesday, appears to show officers "clowning around" during a raid on a suspect's home. There are also allegations that items seized during search operations later appeared on the internet auction site eBay.

Matrix leads Merseyside Police's fight against drug-related gun and gang crime, which has blighted the Liverpool region.

The unit played a significant role in targeting the gangs associated with the murder of 11-year-old Rhys Jones, gunned down in Croxteth in August 2007, and have been credited with a 26% reduction in firearms incidents in the last year.

Merseyside Police's assistant chief constable Andy Ward said: "I want to be absolutely clear - high standards of professionalism are non-negotiable within Merseyside Police. Any suggestion that officers are not meeting those high standards is taken seriously and thoroughly investigated."

Three officers - a sergeant and two Pcs - were arrested for misconduct in March in connection with allegations that items seized during raids later appeared on eBay, the force said.

A further three Pcs were suspended and interviewed under caution last month after the mobile phone picture emerged during the course of those investigations, while two senior Matrix officers were also suspended from duty in connection with "wider managerial issues".

Mr Ward said: "I would stress that no charges have been brought against the three arrested officers and a thorough criminal investigation is ongoing."

Merseyside Police had also imposed a shake-up of Matrix officers to restore public confidence in the unit, he added.