Jesus' tomb was sealed and guarded by Roman soldiers who were then driven off by angels.
(Matthew 27:62-66 NIV) The next day, the one after Preparation Day, the chief priests and the Pharisees went to Pilate. {63} "Sir," they said, "we remember that while he was still alive that deceiver said, 'After three days I will rise again.' {64} So give the order for the tomb to be made secure until the third day. Otherwise, his disciples may come and steal the body and tell the people that he has been raised from the dead. This last deception will be worse than the first." {65} "Take a guard," Pilate answered. "Go, make the tomb as secure as you know how." {66} So they went and made the tomb secure by putting a seal on the stone and posting the guard.
(Matthew 28:1-4 NIV) After the Sabbath, at dawn on the first day of the week, Mary Magdalene and the other Mary went to look at the tomb. {2} There was a violent earthquake, for an angel of the Lord came down from heaven and, going to the tomb, rolled back the stone and sat on it. {3} His appearance was like lightning, and his clothes were white as snow. {4} The guards were so afraid of him that they shook and became like dead men.