OTTAWA -- Two former prime ministers have received their first doses of the COVID-19 vaccine.

Ottawa mayor Jim Watson tweeted photos of Joe Clark and Jean Chrétien receiving shots at the vaccination clinic set up at Ottawa City Hall.

"I feel like there is something very Canadian about our leaders lining up with everyone else to get their COVID-19 vaccine," Watson said on Twitter Wednesday morning.

Clark, 81, and Chrétien, 87, were among the many residents who received COVID-19 vaccines Tuesday at one of the four community clinics in the city. The City said last week that more than 20,000 people had booked appointments for vaccines through Ontario's online booking portal.

The system has had its share of issues, however. More than 3,000 appointments were double-booked last week, leading the city to open an extra community clinic in Orléans and expand the clinic in Nepean to deal with the excess capacity. On Monday and Tuesday, as the province expanded their booking system to include residents 75 and older, several people told CTV News Ottawa that the portal was not accepting bookings for second shots and so they couldn't confirm their first either.

Ret. Gen. Rick Hillier, who is leading Ontario's vaccination campaign, told reporters Tuesday that the issues with the booking system should be resolved by Tuesday evening.