A pay strike by doctors at government hospitals at Nigeria's main city entered a third day Wednesday but the authorities accused the strikers of "blackmail".
Ibrahim Olaifa, chairman of Lagos State Medical Guild, said the the strike was over wages and outdated facilities.
Olaifa alleged in a radio interview that government agents had launched "vicious attacks" on some doctors who support the strike.
A doctor who was beaten up on Tuesday is critically ill in a Lagos hospital, he alleged.
Lagos State government spokesman Segun Ayobolu told AFP that all the demands of the doctors have been met and that their strike was "sheer blackmail."
"The strike is political and we shall not succumb to their blackmail," he said.
Hakeem Bello, another senior government spokesman, said the strike was "needless, unwarranted and unethical."