Busy day? Here are five stories popular with Globe readers to help you catch up.
Theories abound over Nemtsov's killing
Russian investigators are looking into possible motives for Boris Nemtsov's murder, but none are said to be related to the fact he was one of President Vladimir Putin's most outspoken opponents, Mark MacKinnon reports.
Mr. Nemtsov's friends blamed the former deputy prime minister's death on the air of hatred and fear in today's Russia.
No suspects had been named in the case as of Sunday night.
Dalhousie dentistry students release open letter
The male students from the Facebook group say in the letter they know any meaningful apology requires "much more than saying 'sorry'."
The statement comes as a decision on the students' academic future is expected soon.
Physician prescribes exercise for heart health
Heart disease is the number one killer of women in Canada, but it can be prevented with exercise, Heather Ross writes.
A fit, strong heart will likely make any heart-disease treatment and other injury recovery easier.
Start slow with a goal of 10 minutes a day. Then address and manage your stress, and sleep more, not less. See more tips here.
TSN apologizes for inappropriate tweet
TSN has apologized for an insinuating fan tweet about Leafs forward Joffrey Lupul and Dion Phaneuf's wife, actress Elisha Cuthbert. The tweet accidentally made it on the network during its NHL trade deadline coverage.
"It should have never, ever gone to air."
Lupul responded with his own tweet: "TSN just a poor mans TMZ. Embarrassing."
Tunnel or Man Cave?
Toronto's mystery tunnel has been solved: Turns out two men just wanted to dig a hole to "hang out" in.
"You think about a kid making a fort, digging a hole — add 15 years to that," police said.
Though they've lost their man cave, the pair won't have to worry about any criminal charges. Police have determined there was no threat to public safety.
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