The accused Gurbeer Singh Beera was arrested late Thursday night. With the arrest of Beera, four accused have so far been arrested in the case, Amritsar Police Commissioner Ram Singh said on Friday.
Police is looking for the fifth accused Sandeep Sunny.
On Thursday, local SAD leader Ranjit Singh Rana and his two accomplices were arrested while an SHO was dismissed for his alleged failure to act on the girl's eve teasing complaint.
The policeman Ravinderpal Singh was killed on Wednesday after he asked the youths, including the SAD activist, who used to allegedly tease his daughter, to stop harassing her.
The cop had reached the spot after being informed by his 23-year-old daughter, who had earlier also complained that she was chased and teased by these youths.
After the crime, police had registered a case under various Sections of the IPC and the Arms Act against Rana, Gurveer Singh and another accused.
The ASI was posted at Gharinda police station under Amritsar rural district.
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