Lowell Line Train 336 (11:22 am from Lowell) is operating 5-15 minutes behind schedule between North Billerica and North Station due to a mechanical issue. Started Until Affected direction: InboundLowell Line Train 335 (11:20 am from North Station) is operating 5-15 minutes behind schedule between Anderson/Woburn and Lowell due to a train with a mechanical issue ahead. Started Until Affected direction: Outbound