The police on Sunday arrested Zubaida, 48, in connection with the murder of her husband in an acid attack on April 20.
Basheer Pothancheri, 52, had succumbed to burns at Government Medical College Hospital, Kozhikode, on April 22.
Zubaida was arrested after a week-long investigation conducted by a special police team led by Circle Inspector A. Premjit.
Unidentified person
She had earlier told the police that an unidentified person had barged into their house at Munduparamba, near here, and attacked her husband with acid on the night of April 20.
The police had questioned Zubaida many times. There were discrepancies in her statements that raised suspicion among the investigators.
The police said they had zeroed in on her by resorting to scientific investigation methods.
They said the accused had tried to incriminate a few persons here with the intention of misleading the investigators.
All of them were questioned and their involvement was ruled out.
The police also examined thousands of telephone records in connection with the case.
Zubaida finally confessed that she had attacked her husband, and helped the police recover the container in which she had procured the acid.