West Midlands Police is to lose 620 front-line officers as a result of spending cuts, official inspectors have revealed.

The huge reductions come after the force was ordered to find £120 million in savings.

New figures published by HM Inspectorate of Constabulary (HMIC), the official police watchdog, reveal the effect of the cuts on front-line services.

The force has set out plans to lose 1,850 employees, including 1,060 police officers, 20 police community support officers and 770 civilian staff.

But the Government insists that it should be possible to cut police numbers without cutting front-line services by making better use of the officers who are left.

The new report shows that in fact, the number of police working on the front line - defined as “those who are in everyday contact with the public and who directly intervene to keep people safe and enforce the law” - will also fall.

Front-line police numbers will drop from 7,450 in March 2010 to an estimated 6,830 by March 2015.

However, the report by HMIC also praises West Midlands Police for improving the way it operates. It highlights increased co-operation with Staffordshire Police, with the two forces sharing computer technology, and the force’s focus on neighbourhood policing.

Birmingham MP Steve McCabe said: “We’ve been consistently told that these cuts would not damage front-line policing and but here are the figures in black and white showing that they will.

“People are being asked to do more with less and unfortunately this is going to affect the quality of the service the public receives.”

The number of officers employed by West Mercia Police in front-line roles will fall from 2,080 in March 2010 to an estimated 1,970 by March 2015.

The number for Staffordshire Police will fall from 1,790 to an estimated 1,610, and for Warwickshire Police it will fall from 810 to an estimated 670.