Srimad Bhagavatam Canto 10, Chapter 55, Text 03

SB 10.55.3

tam sambarah kama-rupi
 hrtva tokam anirdasam
sa viditvatmanah satrum
 prasyodanvaty agad grham
 
Translation: 
 
The demon Sambara, who could assume any form he desired, kidnapped the infant before He was even ten days old. Understanding Pradyumna to be his enemy, Sambara threw Him into the sea and then returned home.
 
Purport: 
 
Srila Visvanatha Cakravarti points out that according to the Visnu Purana, Pradyumna was kidnapped on the sixth day after His birth.
Srimad Bhagavatam Canto 10, Chapter 55, Text 02
Srimad Bhagavatam Canto 10, Chapter 55, Text 04