MANAMA, Sept 18 (Reuters) - Bahrain's ministry of interior said on Thursday it had released human rights activist Maryam al-Khawaja from detention as she awaits trial, amid international criticism of her treatment. A tweet from the ministry said a travel ban had been imposed on Khawaja and her lawyer Mohammed al-Jishi confirmed via Twitter she had been freed and was on her way home. Khawaja, who has joint Bahraini-Danish citizenship, has been charged with entering the Gulf island state illegally, assaulting a policewoman at the airport and insulting King Hamad. ...