Mouse droppings. Exposed wiring. External padlocks on bedroom doors. A second-floor porch tilting at a precarious angle.
These were just some of the violations city inspectors found over the weekend in apartments where college students rushed to organize clothes, books, and furniture for the fall semester.
Outside a rundown house on Highgate Street in Allston, Mayor Martin J. Walsh said at a news conference Monday that officials had found 120 housing violations and issued 21 tickets of $300 each for unsafe or unsanitary units and 1,100 tickets for code violations.
“The bottom line is the city of Boston is being proactive,” he said. “We are getting on top of student housing now, before the problem gets more dangerous.”
Walsh said 50 inspectors had prowled the neighborhood in the days leading up to move-in day, armed with housing lists provided by colleges and universities, to address concerns about student apartments.
The increased vigilance follows a Globe Spotlight Team series on overcrowded, unsafe, and sometimes illegal off-campus apartments, including one on Linden Street, where a Boston University senior, Binland Lee, died in her illegal attic bedroom during an April 2013 fire.
Inside 24 Highgate St., a city inspector, whom officials asked the Globe not to name out of concern for her safety, pointed out issues to new tenants.
“This here’s a big no-no,” the inspector said, pointing to a padlock on a bedroom door, a potential fire hazard.
“Have you guys noticed any mice droppings?” she asked, leaning over the toilet in the first-floor bathroom. She pointed to the dark pellets. “You have mice,” she said.
In the backyard, a city official showed reporters a dead rat lying in the dried grass.
Pratik Singh, a Boston University junior who was moving into the house, said that it had appeared to be in good shape when he and his roommates first saw it, but the outgoing tenants “completely trashed the place.”
“As a student group, they didn’t do a very good job of maintaining the place, and the landlord didn’t do a very good job during the move-out process,” said Singh, 20.
He said his bedroom wasn’t too bad, compared to the others. “I walked into some of my other roommates’ rooms, and it was absolutely filthy, disgusting.”
Roommate Asees Binepal, also a junior at BU, said they had first seen the house at night, when any damage may have been less noticeable.
“It’s just sad that they made us sign an obligation to pay rent on the first of the month and they can’t even uphold their own moral obligation to maintain the place,” said Binepal, 20.
Binepal and Singh are among six students planning to live in the six-bedroom home, in violation of a city zoning rule barring more than four full-time undergraduates from sharing a house or apartment.
Kate Norton, Walsh’s press secretary, said in an e-mail that the city is prepared to issue citations for overcrowding, but that they “are not our highest priority when compared to the atrocious living conditions that some of these students are facing. Our first priority is always any issue related to life safety.”
Norton said city officials were set to deliver violation notices to a representative of the Highgate Street home’s owner on Tuesday. The owner did not respond to a reporter’s request for comment on Monday.
BU sophomore Henry Heilbroner spent Monday morning helping his brothers from an unofficial fraternity move from an apartment on Wadsworth Street to Pratt Street, where another six men plan to share a six-bedroom duplex.
Heilbroner, who lives on campus, said he was unaware of the zoning ordinance.
The 20-year-old said his friends’ new place, which rents for $5,000 a month, had been used as a fraternity house by the previous tenants.
“It’s not in terrible shape or anything like that,” he said. “It’s just kind of dirty, could probably use a paint job.”
On Linden Street, building inspector Brian Ronan declared a leaning second-floor porch to be “unsafe and dangerous . . . in imminent danger of collapse” and ordered a door to the porch to be covered in plywood and sealed.
Behind the house next door, John Meaney, assistant commissioner of Inspectional Services, posted notices on discarded mattresses, warning of the dangers of bedbugs.
Mark O’Brien, owner of a neighboring three-decker, praised the city’s work.
“They’re cracking down on the problem areas, which is great,” he said.
“They’re doing the right thing.”
■ Correction: Because of a reporting error, an earlier version of this story misspelled the name of Asees Binepal, a junior at Boston University.