DUBAI: A young Bahraini jailed for taking part in anti-government protests last year died in custody on Tuesday after being taken to hospital for treatment of a hereditary disease, the interior ministry said.

The interior ministry said on Twitter than Mohammed Mushaima, who was serving a prison term, was pronounced dead at a government hospital, where he was admitted on August 29 "for treatment from sickle-cell anaemia."

The major Bahraini opposition bloc Al-Wefaq confirmed Mushaima's death, saying he "passed away in custody today (Tuesday) while serving a seven-year sentence for participating in pro-democracy demonstrations."

Lawyers said they had asked the court earlier to release 24-year-old Shiite Mushaima due to his "bad" health, but the court rejected their request.

Sickle-cell anaemia, a genetic disorder in which red blood cells form an abnormal sickle shape, is an inherited illness common in Bahrain where the marriage of close relatives is frequent.

Several other anti-regime activists have died of the disease while in custody, according to the government, including two in April 2011, prompting Human Rights Watch to call for an investigation.

In September of last year, the authorities said another man, whom the opposition claimed died after being tear-gassed, had passed away due to "acute respiratory" problems resulting from sickle-cell anemia.

In August, Bahrain opened a sickle-cell clinic at the government-owned Salmaniya Medical Complex which announced Mushaima's death on Tuesday.

Thousands of people, mostly from the majority Shiite population, took to the streets last year to call for reforms in the kingdom ruled by the Sunni Al-Khalifa dynasty.

The kingdom has continued to witness sporadic demonstrations, mostly outside the capital, since it crushed the protest movement in a bloody crackdown in March last year.