VISITS TO PRE-REMOVAL CENTRES-PROBLEMS WITH THE PROCEDURE OF RETURNS administrative detention, according to the case law of the European Court of Human Rights (case Saadi v UK, 2008, App. No. 13229/2003, paragraph 78). ⇢ D etention at pre-removal centres without procedures of first reception having previously occurred. Specifically, in 2017, the phenomenon of detention of immigrants appears for a period of up to 3 months at the three Pre-removal centres in the region of Eastern Macedonia-Thrace before they are then taken into the Reception and Identification Centre (RIC) of the Evros, a fact which lead the Ombudsman to emphasize to the Greek Police the explicit legal provision12 for the reverse procedure, so that the vulnerability and the registration of the claim for asylum of the newly arrived people can be examined before they undergo the procedure of detention towards return. Moreover, it is noted that in 2017 two new Pre-removal Centres were established on the islands13 in places that then create a problematic co-existence of the detention centres with the centres of first reception and identification (RICs). The afore -mentioned increase in the number of detainees by 60% in the Pre-removal centres of the country in 2017 supplements the picture of the generalisation of detention with a view to return, despite the fact that the Directive on Returns views it as an exceptional measure whereby its implementation is subject to the proportionality principle, which prescribes“ a gradation of the measures to be taken in order to enforce the return decision”14. 12 Article 9, paragraph 1 and 14 paragraph 1, Law 4375/16. 13 On Kos island, wit a capacity of 500 places, and on Samos where it does not function yet. 14 Decision CJEU El Dridi, C-61/11 PPU, 28.4.2011 18