Police in riot gear cleared several large crowds gathered around Fenway Park early today after the Red Sox won their second World Series title in four years. Police spokeswoman Elaine Driscoll said 37 arrests were made in the city, mostly for disorderly conduct. No serious injuries were reported. An unruly crowd flipped a pickup truck to its side near Fenway Park and at least one car fire was reported. Young people sprayed each other with beer and some climbed street signs or utility poles. “Two World Series in four years is pure heaven,” said Andrew Dumas, a Boston University student from West Boylston. Police shut down access to Kenmore Square, near Fenway, as Game 4 neared its end in Denver Sunday night. The Red Sox won the game 4-3, touching off celebrations around New England. Boston authorities cracked down on rowdy sports celebrations after an Emerson College student was struck and killed by a pepper pellet fired by police into an unruly crowd celebrating the Red Sox’s 2004 victory over the New York Yankees in the American League Championship Series. On Sunday, hundreds of police officers took positions on foot, bicycle and horseback around Fenway, hoping to discourage fans from congregating around the ballpark. The police department had announced it would have more than 50 cameras trained on the city to record any vandalism. Elsewhere around the region, some 1,500 University of Massachusetts- Amherst students poured out of their Dormitories after Boston completed its sweep. The university said on its Web site that the crowd was boisterous but peaceful, with no damage reported. Six people were arrested for disorderly conduct or for failing to obey a dispersal order that was issued at about 12:45 a. m. One person suffered a minor injury when he fell to the ground while body surfing. In Durham, N.H., several thousand University of New Hampshire students gathered on Main Street, many carrying brooms and chanting “sweep, sweep, sweep.” Several dozen police officers, some in riot gear, pushed the crowds back toward campus and no arrests or injuries were reported. The victorious Red Sox were expected to arrive back in Boston at about 3:30 p.m. today and head to Fenway Park. Boston Mayor Thomas Menino said the city would meet with team officials later in the day before announcing details of a public celebration, possibly as early as Tuesday. Menino said he expected the parade to be similar to the “rolling rally” that was held after the 2004 title, in which players rode around the city in Duck Boats.