Police in Dresden have called for help from the public after a mosque was vandalized in the east German city amid a growing intolerance against Muslims in the country.Police said Friday they had launched an investigation after insulting messages concerning Prophet Mohammad were written on the walls of the Marwa mosque in Dresden, a stronghold of the recently founded anti-Islam movement PEGIDA, early Thursday morning.Officers said they had no concrete information about the attack and urged the public to help locate the vandals.The mosque had been named after the late Egyptian Muslim Marwa Elsherbiny, who was killed in Dresden six years ago by a right-wing fanatic.