Were the People of Prophet Loot Really Homosexuals?

I've been searching through Muslim texts, looking for authentic, well-established proof that Prophet loot's townsmen were homosexuals. So far, I couldn't find anything that clearly mentions such. The Quran doesn't say they did homosexuality, rather Allah uses the term 'fahisha.' And another thing is, if they were destroyed for homosexuality, than why was his wife also? I suspect that people are basing their conclusions based on Biblical references and not Islamic. Hence, does anyone know of any Islamic evidence clearly stating they were homosexuals?