New Delhi, Feb 22 (IANS): Prime Minister Narendra Modi on Tuesday expressed deep grief over the loss of lives in the tragic factory mishap in Himachal Pradesh.

The Prime Minister also announced an ex-gratia from the Prime Minister's National Relief Fund (PMNRF) for the victims.

"The accident at a factory in Una, Himachal Pradesh is sad. My deepest condolences to the families of those who have lost their lives in this. Along with this, I wish a speedy recovery to all those injured in the accident," the Prime Minister's Office tweeted, quoting Prime Minister Modi.

"Rs. 2 lakh each from PMNRF would be given to the next of kin of those who lost their lives in the tragic factory mishap in Himachal Pradesh. Rs. 50,000 would be given to the injured," it added.

At least seven people were killed and 12 others severely injured in a blast at a fireworks factory in Himachal Pradesh's Una town. Most of the victims are migrant workers.

Una Deputy Commissioner Raghav Sharma told the media that the incident occurred in the Bathu industrial area. The injured were rushed to a government hospital in Una. Fire department, police personnel and rescue workers were present at the spot. The cause of the blast was yet to be ascertained.