From Cubs games to the Bank of America Chicago Marathon, Chicago officials say stepped up security plans have been and will stay in place for major events happening in the city.

As Grant Park prepares to host one of the city's largest outdoor events, the Bank of America Chicago Marathon, drawing more than 40,000 runners and hundreds of thousands of spectators, Mayor Rahm Emanuel said it's too early to tell if any changes will be made to marathon security in the wake of the Las Vegas shootings.

"Remember, we started changing what we were doing after the Boston Marathon... and we upped our game dramatically," Emanuel said.

Marathon organizers said Vegas remains at the top of their mind, but they're confident of the security plan they have in place and will continue to fine-tune it before Sunday.

"As we enter the final week of preparations for the 40th running of the Bank of America Chicago Marathon, the horrible events that took place in Las Vegas on Sunday are weighing heavily on our hearts," Executive Race Director Carey Pinkowski said in a statement. "We extend our deepest condolences to the victims, their families and all who have been affected by this national tragedy. We also understand how many who plan to participate in Sunday's celebration may have some concerns about public safety in the wake of Sunday's events." 

Pinkowski said organizers will be discussing with authorities what, if any, adjustments will be made following the deadly concert shooting. 

"And, on race day, we will be working alongside the Chicago Police Department and many others in the law enforcement community, as we do every year, to keep our event, our participants and our city safe," he said. "We remind everyone on race day to report any suspicious activity to law enforcement immediately. And, we encourage all participants to join us on Sunday for what is always an uplifting, joyous celebration of the human spirit."

A planning exercise with both city officials and Chicago Marathon race organizers is slated to be held Tuesday.

"The planning exercise, with participation by both City officials and race organizers, is designed to analyze potential emergency events and existing emergency response plans to determine if changes or enhancements to the response plans are needed," the mayor's office said in a statement. "Chicago's emergency response plan has been recognized as a best practice by federal and international industry officials."

The Marathon won't be the only big event taking place this week in Chicago.

The Cubs will also kick off their first playoff appearance at Wrigley Field this postseason, drawing large crowds of fans looking to cheer on the beloved North Siders.

But a Cubs spokesperson said the team has been discussing postseason preparedness with the city for weeks.

Home to festivals like Lollapalooza, Pitchfork and more, Chicago is no stranger to big outdoor events.

Emanuel said the city has run six active shooter drills in the past year involving police, fire, OEMC and area hospitals.

In Rosemont, near Chicago's O'Hare International Airport, public safety officials said the village "continually trains and prepares for any number of emergency situations.

"[The Rosemont Public Safety Department] understands the village of Rosemont is in a unique area with multiple entertainment venues in a hub for tourism," the department said in a statement. "As such, we are constantly reviewing security plans and protocols, along with emergency medical training, planning and scenarios."