"Accused Rajkumar Tiwari was arrested in connection with the attack on Michelle Marks, a US national," a senior railway police official told PTI.
Tiwari had slashed the victim on her neck and cheek when she refused to part with her i-Phone while travelling in a first-class ladies' compartment of a Borivali-bound local train at about 5 pm on August 18.
The accused had jumped out of the train as it slowed down at Charni Road railway station.
The victim, who resides at Goregaon alongwith her brother and two others, works with an NGO and has been in Mumbai since a year. On the day of the attack, she had gone to Colaba for a prayer meet.