At least 69 people have died after drinking homemade beer during a funeral in Mozambique, and officials say they suspect the traditional brew was poisoned during the day-long event.

The traditional grain-based brew known as pombe has also put almost 200 people in hospital following the ceremony in the village of Chitma in western Mozambique, officials said.

Among the fatalities received at a local morgue were the owner of the drink stand serving the beverage, her daughter and nephew, they said.

"As we prepared to determine the cause of death of people we began to receive a lot of people with diarrhea and other muscle aches," local health official Paula Bernardo said. "After that we began to receive dead bodies from several neighborhoods."

People who drank the brew -- a fermented mixture of sorghum, bran, corn, and sugar -- only during the morning of the ceremony showed no signs of illness, while those consuming it in the afternoon started becoming sick the next day, leading officials to suspect the drink was poisoned at some point during the funeral ceremony.

There was some initial speculation that beer might have been contaminated with crocodile bile, although experts doubted that was the cause of the deaths and illnesses.

"The use of bile is not uncommon in the production of local or poor quality beer but is not known to be toxic to the extent this outbreak shows," Christian Lindmeier, a World Health Organization spokesman, said in a statement.

While samples obtained from the beer and from victims have yet to be tested, samples sent to the National Laboratory in the Mozambique capital of Maputo reportedly contained "suspicious objects found inside the drum" in which the beer was kept.

It is also being suggested the beer might have been contaminated by plant extracts called cardiac glycosides, commonly known as digitalis.

Drugs from these extracts are still used to treat people with heart failure and heart rhythm problems, but in large doses the glycosides can slow the heartbeat to zero.

It can also bring on symptoms including nausea, abdominal pain, vomiting and diarrhea, consistent with reports coming from health officials in Mozambique about people admitted to hospital there.

The region of the country where the poisonings occurred is home to around a dozen varieties of plants that can yield cardiac glucosides, experts said.