The authorities in Iraq say they have uncovered an al-Qaeda plot to use chemical weapons, as well as to smuggle them to Europe and North America.
Defence ministry spokesman Mohammed al-Askari said five men had been arrested after military intelligence monitored their activities for three months.
Three workshops for manufacturing the chemical agents, including sarin and mustard gas, were uncovered, he added.
Remote-controlled toy planes were also seized at the workshops.
Mr Askari said they were to have been used to release the chemical agents over the target from a “safe” distance of 1.5km (0.9 miles), reports the BBC’s Rami Ruhayem in Baghdad.
All of the arrested men had confessed to the plot, and said they had received instruction from another al-Qaeda offshoot, he added.
As the defence ministry spokesman spoke on Iraqi TV, footage was shown of four men with black hoods on their heads, our correspondent adds. Three of them were wearing bright yellow jumpsuits and a fourth was in a brown jumpsuit.
Soldiers wearing gas masks hold bottles containing chemicals.