THE HAGUE, Netherlands (AP) -- A Dutch investigating judge on Tuesday ordered the continued detention of two men arrested on suspicion of possessing and attempting to sell or use the deadly nerve agent sarin.
The judge said there was insufficient evidence to hold two female suspects beyond Friday. The men can be held for a further 14 days.
The four, three Dutch citizens and a joint Dutch-Turkish national, were arrested last Friday following a tip to police that they may have been trying to sell sarin. The tip triggered a fruitless three-day hunt for stocks of the nerve agent believed to be buried in a field near the southern city of Maastricht. Police also searched the homes of the suspects but found no trace of any sarin.
The identities of the suspects have not been released, in line with Dutch privacy laws.
A lawyer for one of the suspects, Arthur Vonken, told Dutch national broadcaster NOS it was "questionable" that his client's detention was extended even though no sarin has been found.
Sarin, first created by German scientists just before World War II, is a powerful nerve agent. It was used in an attack by the Japanese doomsday cult Aum Shinrikyo on the Tokyo subway system in 1995 that killed 13 people and sickened around 6,000.
Dutch prosecutors refuse to say what the suspects may have wanted to use sarin for or to whom they might have sold it, but say they have no indication it was to have been used in a terror attack.
Prosecutor's office spokeswoman Cindy Reijnders said that even though neither sarin nor any other nerve agent has been found, prosecutors have "strong evidence" that the suspects may have had the deadly chemical in their possession. That evidence includes transcripts of phone taps conducted last week.
Two of the suspects were arrested as they were about to start digging in the field close to Maastricht. Police then spent three days painstakingly excavating 400 square meters (4,300 sq. ft) of the field to a depth of a meter (yard) but found no trace of sarin. Police are still guarding the site, but no longer digging there.
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