This is the account by Josephus in his Antiquities of the Jews describing the death of Agrippa I, which is also described in Acts 12:20-23.
Antiquities of the Jews (19:8:2)
Now when Agrippa had reigned three years over all Judea, he came to the city Cesarea, which
was formerly called Strato's Tower; and there he exhibited shows in honor of Caesar, upon his
being informed that there was a certain festival celebrated to make vows for his safety. At which
festival a great multitude was gotten together of the principal persons, and such as were of dignity
through his province. On the second day of which shows he put on a garment made wholly of
silver, and of a contexture truly wonderful, and came into the theater early in the morning; at
which time the silver of his garment being illuminated by the fresh reflection of the sun's rays
upon it, shone out after a surprising manner, and was so resplendent as to spread a horror over
those that looked intently upon him; and presently his flatterers cried out, one from one place,
and another from another, (though not for his good,) that he was a god; and they added, "Be thou
merciful to us; for although we have hitherto reverenced thee only as a man, yet shall we
henceforth own thee as superior to mortal nature." Upon this the king did neither rebuke them,
nor reject their impious flattery. But as he presently afterward looked up, he saw an owl (22)
sitting on a certain rope over his head, and immediately understood that this bird was the
messenger of ill tidings, as it had once been the messenger of good tidings to him; and fell into
the deepest sorrow. A severe pain also arose in his belly, and began in a most violent manner. He
therefore looked upon his friends, and said, "I, whom you call a god, am commanded presently
to depart this life; while Providence thus reproves the lying words you just now said to me; and
I, who was by you called immortal, am immediately to be hurried away by death. But I am bound
to accept of what Providence allots, as it pleases God; for we have by no means lived ill, but in
a splendid and happy manner." When he said this, his pain was become violent. Accordingly he
was carried into the palace, and the rumour went abroad every where, that he would certainly die
in a little time. But the multitude presently sat in sackcloth, with their wives and children, after
the law of their country, and besought God for the king's recovery. All places were also full of
mourning and lamentation. Now the king rested in a high chamber, and as he saw them below
lying prostrate on the ground, he could not himself forbear weeping. And when he had been quite
worn out by the pain in his belly for five days, he departed this life, being in the fifty-fourth year
of his age, and in the seventh year of his reign; for he reigned four years under Caius Caesar,
three of them were over Philip's tetrarchy only, and on the fourth he had that of Herod added to
it; and he reigned, besides those, three years under the reign of Claudius Caesar; in which time
he reigned over the forementioned countries, and also had Judea added to them, as well as
Samaria and Cesarea. The revenues that he received out of them were very great, no less than
twelve millions of drachme. (23) Yet did he borrow great sums from others; for he was so very
liberal that his expenses exceeded his incomes, and his generosity was boundless.