Top 5 stories at 5

Ping. Ping. It could be the Malaysia Airlines Flight MH370 black box. Officials have what they are calling their “best lead so far” as they search for flight MH370. An Australian vessel says it recorded two pings that would be consistent with the pings emitted from the missing plane’s black box. The next task is fixing the exact position of the transmissions and then lowering an autonomous underwater vehicle to look for signs of wreckage.

First candidate steps up to replace Alison Redford. Rebuilding Alberta’s fractured PC Party isn’t an enviable task, and the first candidate appears to be stepping up. Alberta MLA Ken Hughes resigned his Municipal Affairs minister posting Monday, ahead of a likely bid for PC leadership. Hughes may not be the star candidate many in the party are hoping for, but he does have plenty of political experience. He was a PC MP and then chair of Alberta’s health-care authority before being elected as an MLA. Redford stepped down as premier in March, amid party infighting and questions about travel expenses. Deputy premier Dave Hancock is currently acting as premier.

Russian soldier shoots and kills Ukrainian soldier. Though Russian President Vladimir Putin has praised the mostly bloodless takeover of Crimea, the Ukrainian military is reporting that a Russian soldier has shot and killed a Ukrainian naval officer. The men got into an argument in the dormitory where the Ukrainian soldier lived, according to a Reuters report. The shooting comes as tensions between the two nations escalate even further. On Monday, pro-Russian groups stormed an administration building in the eastern Ukrainian city of Donetsk and declared it as a “people’s republic.”

Measles, measles, measles. Toronto Public Health is warning anyone who may have traveled on a flight from Abu Dhabi to Toronto on March 25 that they could have been exposed to the highly contagious virus, via an unvaccinated baby who was infected. The warning comes as Alberta deals with its own measles outbreak, as does B.C. (more than 300 cases so far), as does New York City (25 confirmed cases this year). Did I mention there is a totally safe, effective vaccine to prevent measles, a disease where one or two people out of every 1,000 infected will die? The message: vaccinate your kids already.

Quebec is still voting. As of 11:30 a.m. Monday, 27.2 per cent of Quebecers had already voted. And 19.27 per cent of registered voters voted in advanced polls, according to Quebec’s chief electoral officer. That’s an increase from the 2012 election, where 16.61 per cent of registered voters voted in advanced polls. Perhaps it means Quebecers are more motivated to vote this time around with all the talk of another referendum, or perhaps it means nothing. All will be clear after polls close at 8 p.m. EST. Check Macleans.ca later for election results and analysis from Martin Patriquin and Paul Wells. Until then, here’s a PT PKP Cruiser that was spotted on the streets of Montreal:

Voting day, take 2: PKP-mobile cruising down Ste-Catherine St. qc2014 pic.twitter.com/7zc20dwPVG

— mirichardson (@mirichardson) April 7, 2014