Bachchan, wearing a brown woollen cap and a blue sweat shirt, was first rushed in an ambulance to nearby Nanavati hospital from his residence 'Jalsa' in Juhu for a check up and scan and was later admitted to Lilavati hospital in suburban Bandra.
The actor was suspected to be suffering from incisional hernia, a recurring problem that has been troubling him since the near-fatal accident on the sets of Coolie in 1982, but there was no immediate confirmation from family or doctors attending on him.
Sources said the Big B, who was shooting for Teen Patti till Friday, had taken ill last night and complained of abdominal cramps.
"Last night he complained of stomach ache for which he was taken to Nanavati Hospital this morning, then he was admitted to Leelavati. At this moment, he is under treatment," Bachchan's secretary Sunil Doshi said.
A large number of fans and media persons, who gathered outside the actor's house on his birthday were shocked to see an ambulance taking the actor on a stretcher accompanied by son Abhishek to the hospital.
Bachchan's daughter Shweta Nanda, daughter-in-law Aishwarya Rai and family friend and SP leader Amar Singh followed the ambulance in a car.
Bachchan underwent a surgery on November 30, 2005 for abdominal infection `Diverticulosis' at the Leelavati hospital.
Earlier in 1982, he had undergone a major surgery after the accident during a stunt sequence for Coolie following which he suffered from myasthenia gravis, an ailment of muscle weakness.
"I am doing fine," Bachchan was quoted as saying by visitors who enquired about his health.
Among those who called on the ailing actor were filmmaker Ravi Chopra and Susan Roshan, wife of actor Hrithik Roshan.
A large number of fans and media persons gathered outside the hospital anxiously waiting to know about the well being of the legendary actor.
Doshi said friends and family were praying for Bachchan's well being. "At this point of time we are focusing attention for his speedy recovery," he said.
Hospital sources said Bachchan was under observation and tests were being carried out. Earlier at Nanavati, stomach and chest X-rays were taken.
Over the years, the Bollywood legend has been coming out of his house especially to greet fans on his birthday.
This year has been an eventful one for the Big B. He had releases like Sarkar Raj, God Tussi Great Ho, Bhootnath and The Last Lear.
Besides, 'The Unforgettable Tour' was his biggest world concert in several years in which he was accompanied by Abhishek and Aishwarya. The tour, spanning over a month, covered the US and Europe.
But, the highlight was that the Big B turned blogger. His blog has been the most visited and is keenly followed by fans.
’Bachchan's health no cause for worry’
Iconic actor Amitabh Bachchan's health is no cause for worry or concern, says Lilavati Hopsital, where he has been admitted after he complained of stomach ache and abdominal pain.
Hospital spokesman Mohanrajan said the actor would soon be up and above and back to work.
He told a TV channel that Bachchan was brought there with complaint of stomach ache and abdominal pain.
"There is no cause for worry or concern. He will soon be up and above and go back to work," he said.
Bachchan's pain relieved
Bollywood superstar Amitabh Bachchan has been provided relief with medicines and investigations were being carried out, a hospital bulletin said.
"Amitabh Bachchan has been admitted to Lilavati hospital today afternoon with a history of abdominal pain which has been relieved by medicines," the bulletin said.
The cause of pain is being investigated by a team of doctors and the report will be available by Sunday morning.
The family - wife Jaya Bachchan, son Abhishek and daughter-in-law Aishwarya and other relatives are present in the hospital.
He has undergone blood investigation and CT scan of the abdomen and reports are awaited, the bulletin said adding that he is in suite number 1101 on the 11th floor.
Further treatment will be decided based on the report.
"We respect the patient's rights and confidentiality and hence would not like to discuss this matter further," the bulletin issued by the hospital spokesperson on behalf of the family added.
‘Big B stable, to remain at Lilavati for at least two days'
Megastar Amitabh Bachchan was said to be stable and doctors have advised him to remain in hospital for at least two days.
"The doctors have advised him to be in the hospital for 48-72 hours and his condition is stable," Bachchan's son and Bollywood star Abhishek Bachchan said.
Abhishek said, "right now he is under medication. He is responding well to medication".
"He (Amitabh) will be in the hospital for 48 to 72 hours. There is slight improvement in his condition. He will be in the hospital for at least 48 hours," Abishek said.
Bachchan, who complained of abdominal pain due to suspected incisional hernia, was admitted to hospital giving anxious moments to millions of fans on his 66th birthday.