With a three-point lead in the championship before the start of the race, Hamilton could leave Singapore with 28 points in hand over Vettel, his main rival.
Race Control will talk to the drivers and assess footage before dishing out any subsequent penalties.
"Obviously it sucks being on the wrong side of the track now, but that's what it is", Vettel shrugged after returning to the paddock.
"I could see Kimi had a great start so I tried not to defend that as it's a long race but after 200 metres everything was done".
Race engineer: "We have lost data from the vehicle so we don't know what is going on".
"I think I need to calm down, but for now I'm very, very happy". I don't know how easy that's going to be when I get home.
Some drivers had expressed concerns about visibility in the wet under floodlights, but the night race had hardly started when it lost three of the first four cars on the grid.
"I have an idea, if we were to do the race again and set the auto up different, something we did on the vehicle would have helped us if we went the other way for how the conditions are".
That cost Hamilton his 10-second advantage over Daniel Ricciardo but as the race became a countdown to the cut-off time, the Mercedes driver held on to take an invaluable 25 points.
Carlos Sainz scored his best-ever result with fourth for Toro Rosso; Jolyon Palmer did the same as he finished sixth for Renault; and likewise Stoffel Vandoorne with seventh for McLaren. But no driver was deemed responsible and no further action was taken.
"But I am sure there will be more opportunities".
"When you're fighting for a world championship you shouldn't do that", the 19-year-old Dutchman said.
It has been a frustrating season for Alonso, who had to retire for the ninth time. But, after Fernando Alonso retired with terminal damage and Daniil Kvyat found the wall, the Safety Car came out for a second appearance.
The remaining cars had to pass through the through the pit lane behind the safety vehicle as the marshals cleared the debris at turn one.