The MLB All-Star Game might have become the site of a mass shooting this week ... had it not been for a hotel housekeeper, who tipped off cops to a huge collection of guns she found in one of the rooms.
Local reports say 4 individuals were arrested this weekend in Denver -- 3 men and a woman -- on illegal weapons charges after cops say they discovered an incredible cache of artillery in their rooms at the Maven Hotel ... just 2 blocks from Coors Field, where the All-Star events will take place this week.
ABC7 Denver reports a total of 16 long guns (AKA, rifles) were confiscated, as well as more than 1,000 rounds of ammo -- plus, body armor.
Their hotel rooms were reportedly on the 8th floor of the hotel ... and their balcony area had a bird's eye view of downtown Denver. Unclear what their intentions might've been, but some are already connecting the dots ... saying this could've possibly been a repeat of the Las Vegas massacre had it not been stopped by the heads-up housekeeper blowing the whistle.
ABC7 says 3 of the 4 suspects have criminal records, and one allegedly posted a scary Facebook message saying they would "go out in a big way."
All the warning signs are there ... and it's terrifying to think what this might have become.