KARACHI — At least five people died and 20 others were injured in an explosion in a multi-story building near Maskan Chowrangi in Karachi"s Gulshan-i-Iqbal area on Wednesday, according to officials from the Edhi Foundation. All injured and deceased were taken to Patel Hospital, the officials added. Footage showed the infrastructure of the building was badly damaged. The blast was suspected to have taken place on the second floor of a building. Eyewitnesses reported that windows of nearby buildings as well as some vehicles were also damaged, according to a report in Dawn. At least two floors of the building in Karachi were severely damaged, creating fears that casualties may rise. Police chief Mushtaq Mahar said the bomb disposal squad and anti-terrorism officials are yet to determine the cause of the explosion. A police official said that initial investigations suggested that the blast could have been due to a gas leak. The official also said that no trace of an improvised explosive device (IED) was found at the scene. Sindh Chief Minister Murad Ali Shah took notice of the incident and directed the Karachi commissioner to submit a detailed report in this regard. He also directed authorities to ensure medical treatment for those injured in the incident and expressed grief over the deaths reported. Speaking to the media, Karachi Administrator Iftikhar Shallwani reiterated that the nature of the blast could only be determined after an inquiry. He stated that officials from the Sindh Building Control Authority were present at the scene. PPP Chairman Bilawal Bhutto-Zardari expressed grief over the lives lost in the incident, a statement by the party said. Bilawal directed officials concerned to provide the best possible medical treatment to those injured and expressed the resolve to protect the lives and the property of those residing in the metropolis. PML-N Vice President Maryam Nawaz said she was "devastated" at the news of the blast. "My sincerest condolences to the grieving families and prayers for the speedy recovery of the injured. I pray that the city of lights never recedes into darkness again and shines with peace and prosperity," she said. PTI leader and Maritime Affairs Minister Ali Zaidi offered "prayers and sympathies" to the victims of the blast. He called on the authorities to conduct a thorough investigation of the incident. A day earlier, five people were wounded when a bomb exploded at the entrance of a bus terminal near Sheerin Jinnah Colony. Police investigators said it was an improvised explosive device (IED) that was planted at the gate of the terminal. According to them, a bicycle rigged with some explosive material [the IED] was parked at the site a little after 3:30 p.m. It blew up wounding five people. — Agencies