The health condition of Chief Minister Mamata Banerjee is stable but is suffering from severe pain in her injured left leg and has a low sodium concentration in blood, doctors treating her said on Thursday afternoon.

She will be under strict observation for the time being, they said.

"The chief minister has severe bone injuries in her left ankle and foot, besides injuries in right shoulder, forearm and neck. She is stable now but is having severe pain in the injured leg," a senior doctor at the state-run SSKM Hospital said.

"The board of doctors evaluated her condition in the afternoon and has decided to conduct a further radiological investigation to exclude any pathology arising out of the post-traumatic syndrome," he said.

The doctors will meet again in the evening for another round of review. "The treatment continues in the same line with correction of hyponatremia. The review board will again meet in the evening," the doctor said.

Hyponatremia is a condition in which the concentration of sodium in the blood is abnormally low.

Banerjee, 66, will not require any surgery for the injuries, the doctor said.

Replying to a question on how long the chief minister is needed to remain at the hospital, the doctor told reporters, "Can't give you any date, the treating doctors will decide depending on her health condition."

Till afternoon, Banerjee underwent around eight different types of blood tests, sources at the hospital said.

The doctors are planning to conduct a series of medical tests, including a CT scan, to assess the degree of her injury, they said.

"A temporary plaster was done on her left ankle. Her ECG report was fine. Her fever has subsided," one of the sources said.

The state government constituted a six-member medical team to treat Banerjee, and doctors conducted an X-ray on the chief minister as soon as she was taken to the hospital from Nandigram on Wednesday evening.

Banerjee is undergoing treatment at special cabin number 12.5 at the Woodburn Block of SSKM Hospital, following an alleged attack on her during the election campaign in Nandigram.