BOSTON (CBS) — One million people could line the streets from Hopkinton to Boston on Marathon Monday. On Friday, law enforcement officers spelled out some of their plan to keep everyone safe.

“I want to make it clear at this time, there are no credible threats to this event at all,” Boston Mayor Marty Walsh stated Friday.

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Even so, officials are still preparing for thorough security throughout the Boston Marathon course on Monday.

At Friday’s security press conference, the mayor, joined by Boston Police Commissioner William Evans, Boston Athletic Association CEO Tom Grilk, and other city officials, detailed different precautions in place.

“We’re working closely with and sharing information with the FBI and our intelligence community locally and internationally,” explained Walsh. “As well as working with the state MBTA police and other local authorities along the route.”

Officials have planned for thousands of police to line the route of the race and use drones to survey from above.

Some officers will be dressed in green vests and others will be undercover.

Over a dozen additional ambulances will also be dispersed throughout the city.

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Police Commissioner William Evans called the safety plan in place “comprehensive” and “multi-layered.”

He asked that spectators arrive early to the course, take public transportation, and try to leave backpacks at home. Checkpoints will be created to allow security officials to check any large bags that are present at the event.

“If an area gets so congested along Boylston Street that our officers are not allowed to move freely behind the crowd, and our bomb-explosive [sniffing] dogs can not move behind the crowd, then certain segments of Boylston Street are going to be closed and we are going to ask spectators to move to another section of the course,” said Evans.

Walsh thanked the spectators and media for their participation in the week’s events leading up to Marathon and the anticipated cooperation on Monday.

He also said, “I have complete confidence in all of our public safety personnel that will keep our city safe from harm and make the marathon as successful as it has been in the past.”

WBZ NewsRadio 1030’s Lana Jones reports 

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