Vaishnava Samhita. Meera Charitam II. Vol II Book VI Chp 13 Shloka 11

जयमल्लःकुम्भकस्य भ्राता कोपेन सम्युतः  |
भ्रात्रे जगाद तत्सर्बं संशयाक्रान्तमानसः  ||

Kumbhaji's brother Jaimal happened to see this. He informed his brother of his suspicion.