The Bulgarian ministers of interior, transport and regional development submitted on Friday their resignations over a bus crash which claimed 17 lives and left dozens injured, the regional development minister said."We have submitted our resignations," regional development minister Nikolay Nankov told a joint press conference, aired by public radio BNR."We carry the political responsibility," interior minister Valentin Radev said, adding that there are many more people responsible for the accident but that he and his peers had obviously failed to organise well work in their ministries.Earlier on Friday, prime minister Boyko Borissov asked Nikolay Nankov, Valentin Radev and transport minister Ivaylo Moskovski to submit their resignations.The reasons for the accident on Saturday, which happened on the road connecting the capital Sofia to the town of Svoge, are still under investigation.