Eleven of more than 60 people, including five Pakistani nationals, who were injured in the blasts in the Samjhauta Express at Deewana near Panipat in Haryana were admitted to the Safdarjung hospital in New Delhi.
Six of the passengers, including five Pakistanis, were in a critical condition, hospital officials said.
The patients who were in critical condition were identified as Harish (15), Samim (14), Abdul Kayum (56) all from Arongi town near Karachi, and Ramesh Kumar (40), Ashok Kumar, both from Sialkote and Mohd Zakir (32) from Bijnore in Uttar Pradesh.
The six have been admitted in the ICU of the hospital.
The other injured persons admitted in the hospital are Nadim (10), Shaukat Ali (40), M Sakil (25), Ruksana (40) and Aksa (8). They are undergoing treatment in the burns ward of the hospital.
There was tight security in the hospital and police personnel were deployed outside the burns ward.
Chaotic scenes were witnessed outside the hospital with the relatives of the injured not allowed to go inside the ward.