Two explosions rocked <a href="https://www.thenationalnews.com/world/africa/uganda-s-opposition-rejects-museveni-s-re-election-as-fraud-1.1148161" target="_blank">Uganda's </a>capital Kampala on Tuesday, injuring a number of people in what police called an attack on the city, the latest in a string of blasts in the country. The explosions took place in the central business district of Kampala near the main police station and the entrance to the Ugandan Parliament, police said. "What we can say [is] this was an attack but who is responsible is a matter that is under investigation," Uganda's assistant inspector general of police Edward Ochom told AFP. Health Ministry spokesman Ainebyoona Emmanuel said on Twitter that the city's Mulago Hospital was treating 24 people, four of whom were in a critical condition. "Following the unfortunate and cowardly act of terrorism, our health workers are working around the clock to save the lives of those injured," he said. The explosion near the police station shattered windows while the one near the parliament building sparked flames that burned near parked cars, Mr Ochom said. "We have dispatched a team," Uganda Red Cross spokeswoman Irene Nakasiita told AFP. The twin attack came after two blasts last month – a bus explosion near Kampala that wounded many people and a bombing at a roadside restaurant in the capital that killed one woman. Police say those attacks were connected and were carried out by the Allied Democratic Forces (ADF), a group that the US in March linked to ISIS. Kyle Spencer, the executive director of Uganda's Internet Exchange Point, told AFP that Tuesday's explosions had sparked panic among many people nearby. "The road to parliament is closed off, there are people just crying. Everyone else is just trying to get away from these areas," he said. "Everybody is evacuating office buildings and the buildings are locking up and not letting anybody inside." Parliament cancelled its Tuesday session after the attacks, asking members to avoid the area "as security forces are working hard to restore order". The premises were placed under tight security, with heavily armed soldiers securing the area as forensics officers in white overalls inspected the blast site. The US embassy in Kampala warned its citizens to steer clear of the area and monitor local news. Ugandan police last month arrested a number of ADF operatives and issued a warning that extremists were believed to be plotting an attack on "major installations". The ADF, historically a Ugandan rebel group, has been accused of killing thousands of civilians in the eastern Democratic Republic of Congo. It is considered by experts to be the most dangerous of more than 120 armed groups that roam eastern DRC, many of them a legacy of two regional wars a quarter of a century ago.