Managua, November 3 (RHC-EFE) -- At least 10 people were hospitalized after deadly Africanized bees attacked visitors to a cemetery in Nicaragua. The local fire department said that 50 others were also attacked by the bees (also known as killer bees), but they did not require hospital treatment.

The bee attack happened on Saturday when workers and family were cleaning the graves in the St. Francis of Assisi cemetery, in Esteli, about 140 kilometers north of Managua. Members of the Nicaraguan Red Cross and General Fire Brigade who came to help were also stung by the bees, according to authorities.

A source at the fire department on Sunday said that the majority of those hospitalized were discharged hours after the attack, having been treated for allergic skin reactions due to bites.

The first victims of the attack of Africanized bees were performing work in the cemetery ready to leave the graves of their loved ones clean on Sunday, when the Day of the Dead is celebrated.

Africanized honey bees known colloquially as "killer bees", are a hybrid of the Western honey bee species, (Apis mellifera), produced originally by cross-breeding of the African honey bee A. m. scutellata, with various European honey bees such as the Italian bee A. m. ligustica and the Iberian bee A. m. iberiensis.

The African honey bee was first introduced to Brazil in the 1950s in an effort to increase honey production, but in 1957, 26 swarms accidentally escaped quarantine and since then have spread throughout South and Central America and arrived in North America in 1985.