LISBON, Portugal — Portuguese health officials say continuing increases in confirmed coronavirus cases in the Lisbon region are due to more tests being carried out in areas identified as hotspots.

The Health Ministry on Wednesday announced 366 new cases nationally — the biggest daily increase in almost four weeks.

Officials said 335 of those new cases were in the Lisbon metropolitan area, while the outbreak is waning in the rest of the country.

The Lisbon total was almost double the number detected in the region the previous day.

Secretary of state for health Antonio Sales said the government’s strategy is to encircle the hotspots, which are in low-income neighborhoods around the capital, and run more tests there.

Construction workers and temporary staff working in the service sector are being especially targeted for testing.