LAHORE Police investigators are grilling several suspects arrested in connection with the kidnapping of US development expert in Pakistan Warren Weinstein as the international aid organisations are profoundly concerned over the incident. A senior official close to the investigators disclosed to this reporter that apparently it seemed a case of kidnapping for ransom. Investigations conducted so far suggest the involvement of gangsters who committed the heinous crime to extort maximum ransom under duress, he said but declined to give any further details. Another official claimed investigation experts had intercepted a phone call wherein the gangsters were talking about ransom for the safe release of Mr Warren, said to be Country Director of a US-based international aid organisation. It could be a hoax call but the investigators are taking it very seriously, he claimed. A US embassy spokeswoman in Islamabad, when contacted, said they were in touch with the law enforcement agencies and the government of Pakistan in this regard. When asked whether someone contacted them or demanded ransom for the safe release of Mr Warren, she said, No, we dont have such information. The Punjab home secretary and the CCPO also met US Counsel General in Lahore Carmella Conroy and discussed with her different aspects of the kidnapping and investigations, police sources said on Monday. Well-informed sources revealed that the foreigners, mostly US nationals working on different development projects here in Pakistan, had almost suspended their activities as the abduction of Mr Warren had jolted their confidence and they are unwilling to travel in the country owing to the security risks. Mr Weinstein, 60, his close associates say, played a key role for introducing several development projects like Small and Medium Enterprises Development Authority (SMEDA) and Pakistan Horticulture Development and Export Broad (PHDEB). He has many heavy projects to his credit, said a friend of Mr Warren who wished not to be named. Also the former consultant to the White House during Bush Administration, Mr Warren is a drunkard and enjoys the company of friends frequently. Extensively traveling was part of his job. He was not a security concerned man. There was no extraordinary security at his Model Town office-cum-residence, his Pakistani close friend further said.