Mexican authorities said they made their largest seizure ever of opium gum -- used to produce heroin -- at a home in the southwest coastal state of Guerrero.

Mexican soldiers confiscated 245 kilos (540 pounds) in the town of Chilpancingo, according to the Secretariat of National Defense.

The seizure has a street value of over $12 million, officials said, adding that the opium gum -- taken from poppy plants -- could have been refined to obtain more than 600,000 doses of heroin.

Two people were detained in the raid.