Image Source: TRIBUNE

A mysterious toxic gas has killed at least 14 people and sickened several others in Pakistan’s southern port city of Karachi, police said on Tuesday. Residents held a protest nearby over the deaths.

Authorities were alerted when residents of Karachi’s Keamari area began rushing to nearby hospitals with severe breathing problems on Sunday night. The source of a toxic gas leak remained unclear on Tuesday. Officials said 14 people have been killed so far, Dawn newspaper reported.