All the suspects arrested in connection with last month’s Manchester concert bombing have been released without charge, police said Sunday, acknowledging that detectives are still not sure whether the attacker had accomplices. Salman Abedi, a Briton of Libyan heritage, detonated a bomb as crowds were leaving an Ariana Grande concert on May 22, killing 22 people and himself. [...] Greater Manchester Police said Sunday that all 22 people arrested on suspicion of terrorism offenses have now been released without charge. Mexican authorities have captured an alleged leftist Chilean militant wanted in connection with the 1991 slaying of a Chilean senator. Top environment officials from the Group of Seven wealthy democracies met Sunday in Bologna, Italy, amid ongoing differences between the U.S. and other members of the club over how to deal with climate change. Scott Pruitt, head of the U.S. Environmental Protection Agency, attended the first few hours of the two-day summit before returning to Washington for a Cabinet meeting, U.S. officials said. [...] nothing had been done to implement the legislation, with the state alleging it was short of funds due to the financial crisis that hit Greece in 2008.