• State Department spox says "deeply saddened" by attack.
• "We extend our heartfelt condolences to those impacted."
• He also says United States supports freedom of expression.

The United States on Wednesday condemned the deadly blast that killed three people, including two Chinese nationals near Karachi airport.

"We condemn the deadly attack near Karachi’s international airport and we are deeply saddened by the reported loss of life and injured victims," State Department spokesperson Matthew Miller said while addressing a news briefing in Washington.

"We extend our heartfelt condolences to those impacted."

The blast near Jinnah International Airport left over a dozen people injured as sources claim it was a suicide attack. The government attributed the attack to the outlawed Majeed Brigade.

The State Department's spokesperson also commented on the protest of the Pakistan Tehreek-e-Insaf (PTI) for the release of the party's founder Imran Khan who faces several cases while being incarcerated for over a year.

He stressed that his country supports freedom of expression, peaceful assembly and association in Pakistan.

"We call on protesters to demonstrate peacefully and refrain from violence, and at the same time," he said, calling on Pakistani authorities to respect human rights and fundamental freedoms.

The spokesperson also stressed that the government ensure respect for Pakistan’s law and constitution, and work to maintain law and order in the country.

To a question regarding the treatment meted out to the PTI founder and his two sisters who were detained during the party's protest in Islamabad last week, Miller refrained from answering by saying: "These are questions for the Government of Pakistan."