Police in Nashua and Manchester, N.H., are looking into whether a robbery and an attempted robbery at motels are related. Police said that witnesses gave similar descriptions for the robber in each case. Nashua police said a man tried to rob a Motel 6 just after 1 a.m. Thursday. He left after the clerk got on the phone with police. Less than an hour later, a Super 8 in Manchester was robbed. The man left with some cash.