(BBC) – Parcel firm Hermes has halted work at a depot in eastern Germany after two male workers died within hours of each other and a third was taken ill.
One of the men died at the depot, the other in a despatch van.
The deaths are being treated as unexplained and police for the moment are treating the circumstances as an unfortunate series of coincidences.
Police tested a poisonous substance found in a parcel but said the amount was not sufficient to cause death.
A 120-strong team from the fire brigade were brought in to investigate the deaths and they inspected the van for possible toxic contamination.
As they opened the packages inside the van, small amounts of a toxic substance were found but police said the quantity discovered was not dangerous.
Post mortem examinations are being carried out on the two men, but police say initial medical reports suggest the two deaths are not linked and there are no specific signs of poisoning.
A criminal case will continue along with an investigation into hazardous substances, police say.