It is narrated from Sayyiduna Ibn Abbas (may Allah be pleased with them both) that whoever commits sodomy with an animal, kill that person as well as the animal.
Hadith Referenceمسند احمد / ومن مسند بني هاشم / 2733
Hadith Gradingحکم دارالسلام:إسناده ضعيف، عباد بن منصور ضعيف ، لسوء حفظه، وتدليسه، وتغيره