Musannaf Ibn Abi Shaybah

Hazrat Tawoos states that when a camel enters the boundaries of the Haram, then indeed its obligation has been fulfilled.

Hazrat Ata says that every sacrificial animal (hadi) which enters the Haram becomes complete on behalf of its owner (its obligation is fulfilled), except for the sacrificial animal of the one performing tamattu, for indeed it is necessary for him that it be slaughtered on the Day of Sacrifice (Yawm al-Nahr).