Boston is moving against landlords accused of illegal dumping. The city has issued tickets for 48,000 violations and collected fines of more than $379,000, double the totals from last year. Nearly $5 million in fines still remains to be paid. The city also has identified 280 property owners owing such large fine amounts that they will have liens placed on their properties in January. The Inspectional Services Department said some of the biggest offenders are banks.