Police are investigating a suspicious incident in Lowther Road, Dunstable, on Saturday.
Two witnesses saw a silver Citroen transit van pull up by the zebra crossing near Ardley Hill Lower School and two men get out at 6.35pm.
They thought they saw the men manhandling a young woman, in her 20s, into the van parked by the crossing. One of the men swore at the witnesses who cycled away. The van drove off towards the roundabout in Langdale Road and the witnesses contacted police as they were concerned for the welfare of the woman.
PC Ben Stone said: “Police reacted quickly to the call but when they arrived at the scene the van had gone and there was no one there. A search of the area has so far yielded no evidence of an incident and we need to trace the woman to ensure she is safe.
“Incidents like this are very rare and unusual which is why we are taking this so seriously and investigating fully. We do not know if the woman knew the men and we are looking for anyone else who witnessed this incident or may have been involved in it to contact us.”
Call 101 or text information to 07786 200011.