Hussaini Dalan and the story of a lost mausoleum

Hussaini Dalan is not only a religious centre for the Shia Muslims of Dhaka, it is also a Dhaka landmark. Founded in 1642, this imambara — an institution that serves as a memorial to the tragedy of Karbala — went through plenty of reconstructions and renovations, but it has not lost its historical significance.

Let’s focus on just one aspect of the historical significance. 
The top photo you are seeing here is a snapshot of the back of the Dalan, taken in 1904. The picture at the bottom is of the same place, taken from more or less the same spot, but clicked at present times — more than a century later.  
At first impression, both the visuals — one from the past and another of the present — look very similar and indeed picturesque as well, with the imposing pillars and the pond. But at closer inspection, the old picture shows a small structure on one side of the main building, which does not exist in the current one! 
This small building was called ‘Muqbara-e-Naib Nazim.’ It was a mausoleum which housed the graves of four Naib Nazims of Dhaka — basically deputy subahdars of sorts — who passed away in the first half of the 19th century, namely Nusrat Jung, Shamsuddaula, Qamruddaula, and Ghaziuddin Haider.
The building has ceased to exist, but the graves are still there, along with a few graves of their family and acquaintances.
Sources: Asudegan-e-Dhaka by Hakim Habibur Rahman; Notes on the Antiquities of Dacca by Sayid Aulad Hasan.