One can find the subject of Lost Tribes of the House of Israel discussed in every renowned encyclopedia, but the pioneer to write on this subject is PromisedMessiahImamMahdi 1835-1908. It is true that the first and primary source on “Jesus did not die on Cross” - rather Jesus was not killed on Cross and later died naturally in India is the pristine Word of God revealed on the PromisedMessiahImamMahdi. Later he formed a committee to investigate in the matter whose members went to the areas where such traces could be found. Promised Messiah has mentioned detail of this from historic records in his book “Jesus in India”, I give hereunder a relevant excerpt from it for the interest of the members: alislam.org/library/books/jesus-in-india/ch4.html
**On the evidence from books of history
which show that the coming of Jesus to
the Punjab and neighboring territories was inevitable **
"The question naturally arises, why Jesus after his escape from the Cross, came to this country what induced him to take such a long journey? It becomes necessary to answer this question in some detail. I have already said something about it, nevertheless, I think it would be helpful to set out the entire topic in this book.
Let it be noted, therefore, that it was extremely necessary, by reasons of his office as a divine messenger, for Jesus (on whom be peace) to have journeyed towards the Punjab and its neighbourhood, for the ten tribes of Israel, who in the Gospels have been called the Lost Sheep of Israel, had migrated to this country, a fact which is not denied by an historian. It was necessary, therefore, that Jesus (on whom be peace) should have journeyed to this country and, after finding the Lost Sheep, he should have conveyed to them his divine message.
If he had not done so, his purpose would have remained unfulfilled, for his mission was to preach to the Lost Sheep of Israel; his passing away from the world without seeking these lost sheep and, after finding them, teaching them the way to salvation, would have been like the case of a man who had been charged by his king to go to a wild tribe in order to dig a well and supply them with water, but who goes instead to some other place, spends three or four years there and takes no steps to search for the tribe. Does such a man carry out the command of the king? No, not in the least; the man cares not for that tribe: he merely looks to his own comfort.
If, however, it is asked, how and why it should be supposed that the ten tribes of Israel came to this country, the reply is that there is clear evidence to that effect, about which even a person of a poor intellect can have no doubt; for it is well known that people like the Afghans and the original inhabitants of Kashmir are of Israelite origin. For example, the people of the hilly tract of Alai which is two or three days’ journey from the district of Hazara, have called themselves Bani Israel from time immemorial; so, also the inhabitants of the Kala Dakah, another hilly tract in this region, take pride in being of Israelite origin."