AMSTERDAM: A former Dutch professional footballer who played for clubs in Portugal, Hungary and England has been shot dead in the latest violence to afflict Amsterdam, police said.Defender Kelvin Maynard, 32, died when two assailants on a motorbike opened fire on his car on Wednesday night in a south-east district of the Dutch capital, a police statement said.Police appealed for any witnesses to the shooting to come forward to assist in the investigation.”The motive is still totally unknown, as is what led up to it and who might have been involved,” a police spokeswoman said. She said that Maynard had had previous run-ins with the police, but would not give any details. “His name is registered in our systems,” she told Reuters.Maynard was playing this season for Dutch amateur club “Alphense Boys”. Previously, he had been with Dutch side Volendam, Portugal’s Sporting ClubeOlhanense, Hungary’s Kecskemeti TE, Belgium’s Antwerp FC and England’s Burton Albion.Tributes flooded in from shocked soccer players and coaches who expressed support for his wife and children.”Kelvin was a big, tough guy, but inside he was a teddy bear,” former coach Joop Gall told broadcaster RTV Drente. “We had regular contact, especially about his sick mother.”Maynard’s murder came on the same day a prominent Dutch lawyer, involved in a case against a gang accused of drug-related killings, was gunned down in front of his Amsterdam home.Alarm has been growing over crime in Amsterdam, a city of 800,000 people where recreational drug use has long been tolerated by law enforcement, creating an underworld of dealers and suppliers which sometimes fuels violence.