Major League Baseball's investigation into allegations that the Astros utilized electronic sign stealing in 2017 will include an examination of conduct during the 2018 and '19 seasons, too, Commissioner Rob Manfred said Thursday.

Speaking to reporters from the Owners Meetings in Arlington, Manfred said they are investigating the allegations "as thoroughly as humanly possible," and that it will encompass the past three seasons.

"We are talking to people all over the industry -- former employees, competitors, whatever. To the extent that we find other leads, we're going to follow these leads," Manfred said.

The sign-stealing allegations were made public in an article published in The Athletic (subscription required), which said the Astros stole signs during 2017 regular-season home games, and possibly the postseason, using a camera stationed in the outfield. Former Astros pitcher Mike Fiers, who was on that '17 team, was quoted in the article confirming the allegations.

The key will be figuring out what happened in the second half of September 2017 and beyond. Two years ago, on Sept. 15, Manfred, after fining the Red Sox for using an Apple watch to steal signs in a game against the Yankees, warned all teams that future infractions regarding sign-stealing will result in heavier penalties, including a possible loss of Draft picks.

Manfred was asked on Thursday if he views that Sept. 15 statement as a line of demarcation in terms of the current investigation of the Astros.

“If you look at how it was handled in the past and you try to penalize in a way that’s consistent with how it’s been handled in the past, I did not believe that the disciplines that have been handed out in the past were in line with the significance of the issues that we are dealing with,” he said. “So I do view this as a line of demarcation here. … I viewed them with a particular level of seriousness.”

Manfred declined to speculate on possible punishments if the investigation proves there was wrongdoing. He also reiterated his earlier comment that there is no timetable for a resolution.

“I was thinking about Spring Training when I said that I would like to be done as quickly as humanly possible,” he said. “I don't think, however, that rushing is a good thing on an investigation like this. You can make a mistake by thinking you're at the end and it turns out later on you weren't really. So we're going to make sure we're at the end before we go.”

Manfred also indicated club owners are in agreement that strong penalties are in order when cheating is proven to have taken place.

"Look at our clubs," Manfred said. "All 30 of them recognize that the integrity of the competition on the field is crucial to what we do every day. And I think that there's wide support across the industry for the idea that when we have a problem in this area, there should be firm, serious disciplinary action that discourages people from engaging in this type of behavior."