The enemies of the people of Judah and Benjamin heard that those who had returned from exile were rebuilding the Temple of the Lord, the God of Israel.
So they went to see Zerubbabel and the heads of the clans and said, "Let us join you in building the Temple. We worship the same God you worship, and we have been offering sacrifices to him ever since Emperor Esarhaddon of Assyria sent us here to live." 1
References for Ezra 4:2
4.2 2 K 17.24-41.
Zerubbabel, Joshua, and the heads of the clans told them, "We don't need your help to build a temple for the Lord our God. We will build it ourselves, just as Emperor Cyrus of Persia commanded us."
Then the people who had been living in the land tried to discourage and frighten the Jews and keep them from building.
They also bribed Persian government officials to work against them. They kept on doing this throughout the reign of Emperor Cyrus and into the reign of Emperor Darius.