Always follow the age-old advice moms have given their children for decades: don't take candy from strangers.
This is the principle 25 German factory workers wish they paid attention to
, after ending up in the hospital from eating sandwiches laced with rat poison that were left on the doorstep of their company.
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None of the victims have shown symptoms of illness thus far, but they are being kept under observation as a precautionary measure, because medical staff said they were unsure of how long it would take for the poison to work, according to local media.
A box filled with sandwiches was left on the doorstep of Mueller-Technik, a car parts company in the north-western town of Steinfeld, Lower Saxony, Tuesday morning. The package contained a note saying the sandwiches were a "gift."
Thinking nothing of it, as workers to buy lunch for each other all the time, employees helped themselves to the cheese and sausage-filled sandwiches.
One employee noticed a strange substance on the lunch and quickly alerted the others. Emergency services were notified and brought anyone who had consumed the contaminated meal to the hospital.
A Berlin laboratory confirmed to the Daily Mail the bread contained traces of rat poison.
Police spokesman Frank Soika said doctors don't believe the poison was distributed in lethal amounts.
"We don't believe the amount of poison used would have been deadly, but it could have caused serious illness," he told the Associated Press.
Helmut Kohake, managing director of Mueller-Technik, said no one on staff is in any sort of serious condition but they are jarred by the incident, during a Wednesday press conference.
"You don't know whether something like this will happen again," he said.
Many rat poisons contain anticoagulants like warfarin
, which kills rodents by causing massive internal hemorrhaging. The Environmental Protection Agency (EPA) reports that such chemicals are less toxic to humans, but can still cause nosebleeds, bleeding gums, and anemia within days of ingestion.
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Mueller-Technik, founded in 1984, makes plastic parts for use in cars, and had about 240 employees.
The leftover rolls were flown by helicopter to a specialist laboratory in Berlin for testing.
The identity of the perpetrator and the motive remains unclear
, according to the BBC.
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