The accused identified as Punit Jain and aged around 30 was arrested in the wee hours yesterday.
The woman was in touch with Jain regarding a project which she had wanted to set up in the city, DCP (East) Amandeep Singh Kapoor said.
They were together for the last couple of days before she was raped on intervening night of Thursday and Friday, he said.
The woman had arrived here from Jodhpur on May 21 for a business trip.
"A pistol was also recovered from Jain's car", he said, adding "He (Jain) is under police custody at Jawahar Circle police station and being interrogated.
