Srimad-Bhagavatam: Canto 10 - Chapter 1 - Verse 17

Sanskrit:

यशोदाया: सुतां कन्यां देवक्या: कृष्णमेव च ।रामं च रोहिणीपुत्रं वसुदेवेन बिभ्यता ।न्यस्तौ स्वमित्रे नन्दे वै याभ्यां ते पुरुषा हता: ॥ १७ ॥

ITRANS:

yaśodāyāḥ sutāṁ kanyāṁdevakyāḥ kṛṣṇam eva carāmaṁ ca rohiṇī-putraṁvasudevena bibhyatānyastau sva-mitre nande vaiyābhyāṁ te puruṣā hatāḥ

Translation:

[Nārada told Kaṁsa:] Yaśodā’s child was actually a daughter, and Kṛṣṇa is the son of Devakī. Also, Rāma is the son of Rohiṇī. Out of fear, Vasudeva entrusted Kṛṣṇa and Balarāma to his friend Nanda Mahārāja, and it is these two boys who have killed your men.

Purport:

Kaṁsa had been led to believe that Kṛṣṇa was the son of Yaśodā and that Devakī’s eighth child had been a daughter. The identity of Devakī’s eighth child was extremely important to Kaṁsa because a prophecy had foretold that her eighth child would kill him. Here Nārada informs the King that the eighth child of Devakī was the formidable Kṛṣṇa, thus implying that the prophecy should be taken very seriously. Having received this information, Kaṁsa obviously will now do everything in his power to kill Kṛṣṇa and Balarāma.