The German Foreign Office on Monday confirmed that two German citizens have been abducted by gunmen in Nigeria's Niger Delta. "We have to assume that the two men were kidnapped," dpa quoted a Foreign Office spokesman as saying. The ministry said it was in contact with the Nigerian authorities to secure their release. The two men, aged 45 and 55, were kidnapped from a beach in Abia State during a day trip on Sunday, reports said. According to a local police official, the two had travelled to the beach on a river without a security escort, as is the norm in the restive area, where kidnapping is common. One of the men lives in Nigeria. The other was working in the country on behalf of a German company.