Three helicopters and two rescue ships rushed through the night to reach the 24-man crew of the Baltic Ace, who were clinging to life rafts in conditions that saw waves as high as 10ft.
The 23,000-tonne car carrier, registered in the Bahamas, collided with the Cypriot registered Corvus J, a container ship, at around 7.15pm (6.15pm BST) some 60 miles from Rotterdam in waters off the southern Dutch coast.
Peter Verburg, a spokesman for the Dutch coast guard told AFP, said the crew had launched life rafts after the collision, and rescue teams were attempting to pluck them from the rafts.
“We are feverishly looking for 11 missing crew members of the Baltic Ace which sank earlier. So far we have rescued 13,” another spokesman, Marcel Oldenburger said, adding that a helicopter with infrared capabilities had joined the search.
In a statement, the Dutch Defense Ministry said two navy patrol ships were aiding in the search. “Helicopters are trying, in (strong wind) and high waves to bring the people to safety,” the ministry said.
By around 10pm BST 13 crew members had been pulled to safety, but 11 were still missing, and it was feared that some were not on rafts but in the icy waters.
Mr Verburg said the 12-man crew of the Corvus J was still on board the ship, which was helping in the rescue operation. “It is badly damaged, but not in danger of sinking,” he said.
It was not clear last night if anyone had been injured in the crash or subsequent rescue attempt.
The Baltic Ace was under way from Zeebrugge in Belgium to Kotka in Finland and the Corvus J from Grangemouth in Scotland to Antwerp in Belgium, according to shipping tracker website MarineTraffic.com.
“At this stage we don’t know what caused the accident,” Mr Verburg said, adding: “Our first priority right now is the safety of the 24 crew members.”
The shipping lane where the accident happened is one of the busiest in the North Sea and an important passing point for ships sailing into the Rotterdam port, Europe’s largest and the fifth-largest in the world, Dutch media reported.
Rotterdam port spokesman Sjaak Poppe said the collision would not affect shipping in and out of the port.