A couple was seriously injured when the bike on which they were riding, fell into a ditch that was dug for waterworks. Another biker too was injured when he rode into the hole. The incident took place at Safilguda in Malkajgiri of Hyderabad. The ditch was dug by Waterworks department workers, who left it open without closing it, locals said. It may be recalled that Greater Hyderabad Municipal Corporation (GHMC) chairman Janardhan had warned the public about roads being dug for laying pipelines. However, the workers should have taken care to at least put up a neon board at the place.