LONDON (Reuters) – British Prime Minister Boris Johnson said on Wednesday there were few things more depraved than the targeting of vulnerable and defenceless people, after Ukraine accused Russia of bombing a children’s hospital in the port city of Mariupol. “There are few things more depraved than targeting the vulnerable and defenceless,” Johnson said on Twitter. “The UK is exploring more support for Ukraine to defend against airstrikes and we will hold Putin to account for his terrible crimes.” (Reporting by Kate Holton, Editing by Kylie MacLellan)