Turkish troops and allied Syrian opposition fighters encircled the Kurdish-held town of Afrin on Tuesday. Afrin, located in Syrian territory, has been the target of an Ankara-led offensive for seven weeks.

In a brief statement, the Turkish military said that the new siege on Afrin had begun on Monday, adding that it had taken control of "critical areas" of the town without giving further details.

Earlier on Monday, Turkey's army asserted that it had taken over half of the area under rebel control.

Read more: Turkey's military offensive against Kurdish-held Afrin: What you need to know

Operation 'Olive Branch'

The wider Turkish operation in Afrin, dubbed "Olive Branch," began on January 20 and aims to drive the Syrian Kurdish group YPG out of the Turkish-Syrian border region.

The YPG has been a close Western ally in the fight against Islamic extremists in Syria. But Ankara labels the YPG a terrorist group and an extension of the banned Turkish-based Kurdistan Workers Party (PKK).

As Turkish troops approached Afrin on Monday, thousands of civilians began to flee the Syrian city and headed toward nearby areas controlled by the Syrian government.

Read more: Who is Salih Muslim, the Syrian Kurdish leader wanted by Turkey?

300,000 people under siege

The UK-based NGO Syrian Observatory for Human Rights said that Turkish forces and their Syrian militia allies have effectively encircled an estimated 700,000 people in Afrin and nearby areas.

Turkish President Recep Tayyip Erdogan said last Saturday that his government planned to expand the offensive against Kurdish rebels in the border areas after the army gains control of Afrin.

Read more: Turkey’s offensive in Syria: Why a muted response from the US and Russia?

jcg/amp (Reuters, AP)

Each evening at 1830 UTC, DW's editors send out a selection of the day's hard news and quality feature journalism. You can sign up to receive it directly here.