Mr Jena said 28-month-old twins -- Jaga and Kalia -- joined at their heads, were separated during a 16-hour-long surgery which began on October 25 morning and ended yesterday, are under round-the-clock observation and the next 30 hours will be crucial for them.
A team of specialist doctors have been engaged to monitor their condition, he added.
The twins, who hail from Milipada village under Phiringia block in Kandhamal district, are craniopagus conjoined twins, joined at their heads, which is a very rare condition.
"The whole of Odisha has been praying for the speedy recovery of Jaga and Kalia. We hope the twin brothers will return Kandhamal after their recovery," the minister said.
Chief Minister Naveen Patnaik in a tweet yesterday had said, "Glad to learn of successful separation of Jaga Kalia at #AIIMS. Congrats to the doctors' team. Pray to Lord Jagannath."
The ruling BJD workers organised a mass prayer in front of the Ram Mandir here yesterday praying for the speedy recovery of the twins.
Odisha Tourism Minister Ashok Panda, Mayor Anant Narayan Jena, MLAs Priyadarshi Mishra, Bijay Mohanty took part in the lamp offering ritual.
Several schools across the state also organised prayers. Students from the Kalinga Institute of Social Sciences (KISS) also held mass lamp offering and prayer at the institute premises yesterday.
A mass prayer was organised at Phiringia in Kandhamal district, the native place of Jaga and Kalia.
"We will organise a prayer session this evening for the twin brothers at the Odia Baptist Church in Phulbani town," said Church secretary Arup Jena.
The conjoined twins were admitted to the AIIMS on July 13 and the first phase of the surgery was performed on August 28.
The Odisha government has sanctioned Rs one crore from the Chief Minister's Relief Fund (CMRF) for the twins' treatment.
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