Alberto Fujimori was taken the hospital on the same day when Peruvian President Pedro Pablo Kuczynski said a potential pardon for him would not be immediate.
Peru's jailed former president Alberto Fujimori was taken to a hospital on Friday after showing signs of hypertension and irregular heartbeat, his doctor said.
The hospital trip comes on the same day that Peruvian President Pedro Pablo Kuczynski said a potential pardon for Fujimori would not be immediate, as had been speculated, but depended on a medical report that will likely be issued by the end of the year.
Fujimori, who turns 79 on July 28, was jailed in 2007 for his role in killings by a death squad targeting supposed guerrillas in the 1990s. He was also convicted of embezzlement and bribery.
"We have brought him to the clinic tonight," Fujimori's physician Alejandro Aguinaga said, adding the ex-leader showed signs of "a hypertensive crisis with arrhythmia" and would be evaluated.
He was undergoing tests after which doctors would determine whether he should remain hospitalised or be transferred back to the police headquarters in a Lima suburb where he was being held.
Protests against possible pardon
Peruvians took the streets on Friday to urge Kuczynski not to pardon Fujimori, who is serving a 25-year prison sentence for human rights violations.
At least 2,000 protesters participated in the march through the streets of Lima, witnesses said.
Kuczynski's promise not to pardon Fujimori during last year's presidential election helped him scrape together a narrow victory against Fujimori's daughter, Keiko Fujimori.
But last month Kuczynski proposed a potential pardon for Fujimori, 78, for health reasons as his finance minister was ousted by Congress, which is dominated by Fujimori's supporters.
"It would be a betrayal. A betrayal of his word and his promise to the families of the victims of the dictatorship," said protest organiser Jorge Rodriguez.
Peruvian law allows the president to offer pardons for Independence Day — celebrated on July 28 — and for Christmas.