Matsyapurana 45.10

45.10

prasenastu gato 'raṇyaṃ maṇiratnena bhūṣitaḥ
taṃ dṛṣṭvā sa hatastena govindaḥ pratyuvāca ha
hanmi cainaṃ durācāraṃ śatrubhūtaṃ hi vṛṣṇiṣu //

Knowing him to be dead, Śrīkṛiṣṇa was dismayed. Some one gave currency to the rumour that Prasena was murdered by Kṛiṣṇa for the sake of the Syamantaka gem. It was insinuated that Prasena went out wearing his priceless Syamantaka gem and was decidedly killed by Kṛiṣṇa, who usurped the jewel from him. Satrâjita, the brother of the deceased, also thought the same.—9-11.