Chandigarh, Sept. 30 -- Armaan Singh, 18, who allegedly shot dead his father, a UT police head constable, at their Sector 22 residence last Friday, had also planned to kill his mother so he could inherit the family property and live comfortably with the girl he was in a relationship with, police said. The teenager, whose police remand ended on Tuesday, was produced in court again, following which his custody was extended by four days. A senior police official who questioned the accused said Armaan, the only child of head constable Nitin Singh and sub-inspector Monica, was eyeing a house in Zirakpur that his father had recently purchased, as well as a 7-8-acre plot the family owned at a prime location in Panchkula's Khatauli village. "Armaan wanted to marry the girl even though he wasn't even 19 yet. His parents had asked him to wait until he was older. This enraged him. He wanted to take a shortcut, get the land and properties, worth crores, in his name and live life on his terms," the senior police official said. "He thought that, being the only child of the couple, he could easily inherit all their property after killing them," the official added. Meanwhile, the man who allegedly supplied the country-made pistol used by Armaan to shoot his father was arrested from Haridwar, Uttarakhand, late Monday night. Identified as Mohammad Shaheen, 28, the accused is a carpenter who allegedly ran an illegal weapons-supply trade on the side. He was arrested following revelations made by Armaan. The teenager had allegedly procured the weapon from Shaheen just 10 days before the murder. Shaheen has also been sent to four days' police custody. Police officials said they would investigate how the two got in touch and whether Shaheen had supplied weapons to others in the tricity. A hunt is also on for a third person who allegedly worked with Shaheen in supplying firearms. Officials familiar with the case said that while the FIR was initially registered under the Arms Act and Section 103 (murder) of the Bharatiya Nyaya Sanhita, additional sections, including Section 115 (voluntarily causing hurt) and Section 61 (criminal conspiracy), will be added following the latest revelations. They said that since Armaan had allegedly attempted to hurt his mother as well, provisions relating to causing simple hurt would also be added. Her medical examination, conducted the same day, showed injury marks on her neck. Police are also treating the killing as "pre-planned", as the accused had allegedly procured the weapon well before the crime. The section relating to criminal conspiracy will therefore also be added, officials said....