A small private plane crashed south of Brussels on Saturday, killing five members of a family including three small children, according to Belgian news reports. The plane had a problem on takeoff, immediately tried to return to the airport in Charleroi, but crashed beside the runway, the website of the newspaper Le Soir reported. According to the news website sudinfo.be, the victims were a 68-year-old grandfather, his 39-year-old daughter-in-law, and his three grandchildren, aged 7, 6 and 3. The victims were from Brussels, and the children's father was on his way to the airport, news reports said. The accident is reported to have taken place around 10 a.m. local time, 0900GMT. The airport has been closed until further notice, its website says. Photographs showed the plane to be partially disintegrated. Belgian Prime Minister Elio Di Rupo expressed his condolences on Twitter, as did Didier Reynders, the country's foreign minister. David Gering, a spokesman for Brussels South Airport, told the broadcaster RTBF that an investigation into the cause of the crash was under way. Charleroi is about 35 miles (60 kms) south of Brussels.