Seven Delhi hospitals and Tihar Jail received bomb threats by email on Tuesday, two days after similar messages were sent to 20 hospitals, the airport and the office of the Northern Railways' CPRO in the capital, officials said.
Nothing suspicious has been found as of now, officials said.
While the Delhi Fire Service said that they received bomb threat calls from four hospitals, the Delhi police said that they received calls from seven hospitals and Tihar Jail.
According to police, the emails were sent from 'beeble.com', a Europe-based mailing service company, with the same content sent to hospitals on Sunday.
The officer said on Tuesday the email had come from the ID "courtisgod123@beeble.com".
The content of the letter read, "I have placed explosive devices inside your building. They will explode in the following hour. This isn't a threat, you have a few hours to disarm the bomb or else the blood of innocent people inside the building will be on your hands."
"The group called 'Court' is behind this massacre," it said.
The officer said the e-mail was sent to one hospital with copies marked to others and Tihar Jail.
According to a DFS official, the spate of calls began at 10.45 am.
The first hospital to call was Deep Chand Bandhu Hospital in north Delhi's Ashok Vihar at 9.45 am. The second call came at 10.55 am from Dada Dev Hospital in Dabri in southwest Delhi, the third at 11.01 am from Hedgewar Hospital in east Delhi's Farsh Bazar and the fourth at 11.12 am from GTB Hospital in Shahdara, also in east Delhi.
The other hospitals, Attar Sain Jain Hospital in Keshavpuram, Chacha Nehru Hospital in Geeta Colony and DDU Hospital in Hari Nagar also received the same mail, they said.
The police officials said that they had received some calls directly at their respective police stations from the hospitals.
A senior police officer said they received a call from Tihar jail about a similar email threat at 1 pm. A thorough check was conducted.
The bomb disposal squad, bomb detection team, fire department and local police rushed to the spot to conduct searches, the officials said.
"The police and the bomb disposal squad have conducted the checking. We have also conducted checks twice. Nothing suspicious has been found so far," said VK Sharma, security officer at Hedgewar Hospital.
Dr Vatsala Agarwal, Medical Superintendent of Deep Chand Bandhu Hospital, told PTI Videos, "We got to know around 10 a.m. when we received an email on our official mail about a bomb threat. Right after, we informed the local SHO, who reached with his team within 5 minutes. The crowded areas were evacuated, but we kept the admitted patients inside."
"However, the emergency treatment was not halted while the checks were ongoing, but everyone was alert. After the bomb squad came and checked the premises, we restarted the OPD," Dr Agarwal said.
Similarly, GTB officials also confirmed receiving the email, stating, "At noon, we received the same email."
Doctor Ravinder Singh, Joint Director of Delhi State Cancer Institute, said, "Like other hospitals, we also received the bomb threat. During this time, to ensure safety, we shifted the maximum number of patients from the OPD who could be moved out, so that the bomb squad could check the area properly."
"Even though the staff and doctors were on high alert, there was no panic and the situation was handled calmly," an official from the Dada Dev hospital said.
This is the fourth time in two weeks that various places, including schools, have received such threats in Delhi.
Before Sunday, when the airport and the 20 hospitals got bomb threats, Delhi's Chacha Nehru Hospital received a bomb threat on April 30. On May 1, about
150 schools got email threats generated from a Russia-based mailing service company.