Yemen’s rebels on Monday released scores of detainees they had rounded up and held for years in rebel-controlled territory, a development that raised hopes of reviving stalled peace talks between the warring sides. The International Committee of the Red Cross said the Iran-aligned rebels, known as Houthis, freed 290 detainees. Franz Rauchenstein, the ICRC’s chief in Yemen, said the Red Cross facilitated the release following a request from the Houthis.