משנה אויף במדבר 28:10

These things in [connection with] the pesah override Shabbat: its slaughtering and the sprinkling of its blood and the cleansing of its innards and the burning of its fat. But its roasting and the washing of its innards do not override Shabbat. Carrying it and bringing it from outside the Shabbat border and cutting off its wart do not override Shabbat. R. Eliezer says they do override [Shabbat].