Praise be to Allah.
We think that in this case you should make the best use of the money and put it to business use so that there will be halaal profits. After that, the mosque can be built with the capital and the profits. You should try to make sure that the people in charge of this project are good and trustworthy people who will make their best efforts. They should try to build this mosque quickly and do whatever is needed. If they cannot succeed in the elections or do not have a vote, then they can work with others and co-operate in matters where nothing haraam is involved. If some of those who are elected are not fit to serve on this committee which is in charge of (the mosque’s) affairs, then the others have to declare that they are not in agreement, and explain the reasons why they do not approve of those people who they think are not qualified to be elected or to vote, so that the people in charge of this charitable project will be good and trustworthy people. With regard to the ribaa, whatever they have taken, they are responsible for it and you have nothing to do with them or the interest payments that they have taken.