While the Lahore Conspiracy Case had already started and hundreds of revolutionaries of the Ghadar Party were already being prosecuted systematically, the british government was acutely aware of their failure to capture the top revolutionaries that were responsible for the planning and execution of the uprising at the highest level in Panjab; Rash Behari Bose, Kartar Singh Sarabha, Dr. Mathra Singh and a few others. While they were already getting secret intelligence about the whereabouts of Dr. Mathra Singh in the Frontier region, they knew very well that Afghanistan offered a safe sanctuary to them and capturing Dr. Mathra Singh was of peak importance at that time. Therefore, in this particular case, rather than the regular correspondence by the Panjab police or CID officers, the Viceroy Hardinge himself wrote a personal letter to Amir of Afghanistan, Habibullah Khan in July 1915 about these two Sikhs, Dr. Mathra Singh and Harnam Singh, “absconders in the Lahore Conspiracy Case”. The Viceroy requested the Amir to arrest them on arrival and hand them over since they were accused of sedition in the Lahore Conspiracy case.
On crossing over to Afghanistan, they travelled from Maidan in Tirah to Pesh Bolak, a village on the road from Peshawar to Kabul. It is situated at the eastern extremity of the desert of Butte Kote, in a district bearing the same name of Pesh Bolak. By travelling this way, they avoided the border crossing at Landi Kotal where they would have faced certain arrest. The normal way would have been to travel from Peshawar to Karapa pass through Mohamand country passing in front of Jamrud Fort that the Sikhs built. Jamrud Fort is visible from a distance like an old battleship. Looking ruggedly majestic with its jumble of towers and loophole walls, the fort containing the grave of its builder, the famous Sikh General Hari Singh Nalwa, who died here in action against the forces of the Amir of Kabul in 1837 AD. Jamrud derives its name from the Iranian emperor Jamshed who ruled here some 2000 years ago. To Ali Masjid by Shadi route to chora-gully defile and further to Bazarak, then downhill to Chahar Chobah pass, and on to Pesh Bolak. Their alternate route however was without the benefit of any road and passed through a barren stony plain, cut up by water-courses. There they stayed at a Gurdwara in the village.
However, after a short stay of a few weeks, they were summoned by the governor of Pesh Bolak and told that they have been called by the Amir of Afghanistan, Habibullah Khan. They were then put in chains and taken on foot over a distance of twenty miles to Jalalabad. They were dutifully presented before the governor of Jalalabad. He got their chains removed to their huge relief but were put under guard with strict restrictions to not venture out of Jalalabad. For their sustenance, the governor started paying them one rupee per day for expenses. They stayed this way in Jalalabad for twenty eight days under suspended sentence. Subsequently they were summoned to Kabul. The distance of 115 miles to Kabul from Jalalabad was covered on foot, the excruciating trip, in chains, lasting over eight days. On reaching Kabul, they were immediately put in jail, where they stayed imprisoned for a few weeks till October 1915 when the Berlin Committee sent a German mission with representatives of the Turkish caliphate and Indian leaders Mahendra Pratap and Maulvi Barkatullah to Kabul. Barkatullah, being an old friend of Dr. Mathra Singh and on becoming aware of the situation, immediately petitioned Amir Habibullah for their release, which was granted. Read more in the book.