Seaway Bank & Trust has filed a lawsuit against Urban Partnership Bank alleging wrongdoing over a mortgage portfolio of more than 1,500 home mortgages with a face value of $154 million. The dispute started late last year when Urban Partnership sold more than 1,500 mortgages originated by its predecessor, ShoreBank, to Seaway. The deal unraveled and Seaway now claims Urban Partnership won’t return a security deposit of several million dollars. At issue was how quickly Urban Partnership wanted Seaway to assume the loans. Seaway said that its bid specified a 120-day period before it could assume the mortgages. But Seaway was informed it needed to take over the loans in 15 days. According to the complaint, the marketing firm in charge of the deal then transferred the security deposit to Urban Partnership without telling Seaway.