JMM President Shibu Soren has been admitted to a private hospital after he complained of heaviness in the chest.
According to sources at the Abdur Razzaque Ansari Memorial Weavers' Hospital, besides heaviness in the chest, Soren complained of high blood pressure.
"Treatment is going on and his medical report is expected to be available by evening," the sources added.
Earlier in the day, Soren, who complained uneasiness, was rushed to the Central Coalfields Limited Hospital. Later, doctors referred him to the Appolo Hospital.
Soren, resigned yesterday from the post of Jharkhand Chief Minister, attended a UPA meeting last night.
Soren had lost the Tamar assembly by-elections last week.
Soren took over the reigns of Jharkhand in August last year and was under a constitutional obligation to win an assembly poll within six months to remain the Chief Minister of the state. But he lost the Tamar assembly election to his main opponent, Raja Peter who was a nominee of the National Democratic Alliance .
Raja Peter of the regional Jharkhand Party an ally of NDA defeated Soren by the margin of 9,062 votes.
Soren was sworn in as the sixth Chief Minister of Jharkhand on August 27, 2008 and won a trust vote in the Legislative Assembly on August 29, 2008.
He previously represented the Dumka constituency of Jharkhand in the 14th Lok Sabha and is the President of the Jharkhand Mukti Morcha (JMM), a constituent of the UPA.
Soren also served as the Minister for Coal in the Union Cabinet before becoming the Chief Minister.