The lid of the tomb of King Uzziah (767 -740 BC). When he died, he could not be buried in the royal tombs because he was a leper.
In the first century BC, because the city of Jerusalem had expanded, Uzziah's tomb had to be moved outside the new city limits. This Aramaic epitaph was erected to mark the king's new burial place, with this inscription, "Hither were brought, the bones of Uzziah, King of Judah. Do not open!"
Uzziah was struck with leprosy because he attempted to offer incense to God, which he was forbidden to do because he was not a priest. This is recorded in the Books of Kings and Chronicles.
"But when he had become strong he grew proud, to his destruction. For he was false to the LORD his God, and entered the temple of the LORD to make offering on the altar of incense. But the priest Amaziah went in after him, with eighty priests of the LORD who were men of valour; they withstood King Uzziah, and said to him, 'It is not for you, Uzziah, to make offering to the LORD, but for the priests the descendants of Aaron, who are consecrated to make offering. Go out of the sanctuary; for you have done wrong, and it will bring you no honour from the LORD God'. Then Uzziah was angry. Now he had a censer in his hand to make offering, and when he became angry with the priests a leprous disease broke out on his forehead, in the presence of the priests in the house of the LORD, by the altar of incense. When the chief priest Azariah, and all the priests, looked at him, he was leprous in his forehead. They hurried him out, and he himself hurried to get out, because the LORD had struck him. King Uzziah was leprous to the day of his death, and being leprous lived in a separate house, for he was excluded from the house of the LORD." (2 Chr 26:16-21).
"The LORD struck the king, so that he was leprous to the day of his death, and lived in a separate house.(2 Kg 15:5).
Because he was a leper, it would have been potentially dangerous for anyone to open the tomb.
According to Josephus the earthquake mentioned in the introduction to the Book of Amos, and mentioned by Zechariah occurred at the moment Uzziah tried to offer incense.