A Nonthaburi mother on Friday confessed to drowning her three-year-old son in a small pond in Ayutthaya out of frustration because she had not been drunk for days, police said.
Rungthip Yothikar, 34, admitted on Friday afternoon that she killed her son after she was questioned by police on Thursday night.
The boy's body was found floating on a small pond in a field of tall grass beside a railway track in Ayutthaya's Phachi district on Thursday.
The woman's relatives in Nonthaburi sought help from Pachi police to search for the boy after Rungthip left home with him on October 14 and returned home on Tuesday without her son.
She claimed that she left home without her son but her relatives saw her leaving home with the boy.
Police said that after questioning, Rungthip admitted she took her son to the spot and drowned him out of frustration because she had not been drunk for days. She said she was an alcoholic.