Police in show of force on New York subway system

A new terror threat against the New York subway raised the spectre of an attack with explosives concealed in a baby stroller and prompted a show of force by the largest police department in the US.

Officials in New York revealed the threat yesterday, saying an FBI source warned terrorists had plotted to bomb the subway in coming days. But Homeland Security officials in Washington downplayed the threat, saying it was of “doubtful credibility”.